#SCSI confusion…
61 messages in this thread
I'd like to try and hopefully straighten out a few misconceptions
about SCSI.
First there was just "SCSI" (1 or I if you like). This was a command
set and an 8 bit interface. "SCSI-II" (2) is an expanded command
set, but is still based on the 8 bit interface. "SCSI-II WIDE" is
the SCSI-II protocol using a 16 bit interface, allowing up to twice
the maximum data transfer rates of 8 bit SCSI (I or II). "SCSI-II
FAST" can be implemented on either the 8 or 16 bit interface, and
means that it supports synchronous (burst) transfers of 10 million 8
or 16 bit transfers per second instead of the normal 5 million.
Most original SCSI controllers were SCSI-I command compatible, using 8
bit interfaces. GVP's Series II HC8 board which has been around for
a few years supports the SCSI-II command set, and is 8 bits wide.
This means in theory it could support up to 5MBytes / second, but it
doesn't due to various hardware limitations in it. It's actual limit
is about 3.5MB/second, I believe, although I could be a bit off on
that figure. Commodore's latest and greatest 4091 is a SCSI-II FAST
8 bit interface card I believe, meaning that it that supports bursts
up to 10MB/second. If such a beast existed for the Amiga, a SCSI-II
FAST *and* wide interface card could support up to 20MB/second.
BUT, before you drool over these big numbers, you need to look at the
reality of what typical drives can ACTUALLY deliver. We at GVP look
at drives all the time, and even the most blazingly fast drives
certainly cannot out perform the 4091 AND MORE IMPORTANTLY, *most*
drives cannot out perform even our lowly HC8 (the Rodney Dangerfield
of controllers it seems these days).
So, my advice – before you decide you MUST have the fastest controller
there is, you should first decide if you're ever likely to shell out
the money for the type of drive that can use it. You might just be
able to save yourself a bunch of money by buying a simple HC8 and put
the money you'll save toward some software perhaps or even a bigger
drive.
I hope this helps…
Regards,
Paul.
May latest issue of ComputerWorld had a full page ad for some SCSI-II FAST WIDE
drives & EISA PC controllers. (I think the manufacturer was Seagate). They
were 3.5 GB drives and had the option of single termination or some other setup
for LAN use that dealt with termination. External drives w/case. 3.5 Gb
drives. No price given.
-Chas
P.S. – They were claiming 20 Mb/s transfer rates.
Hi Chas. Yes, Seagate appears to be making the best SCSI drives right now,
which is obviously in large part due to the fact that they bought CDC (maker of
those wonderful WREN drives, etc). Those 3.5GB drives you mentioned are
probably a) not available yet, and b) HUGE $$. It's not clear to me that many
Amiga users need or can afford that kind of technology. Generally those kind
of drives are used for BIG servers, not loading and saving 24 bit IFF files
<g>.
Regards,
Paul.
True, most Amiga users might not want those drives but….
After seeing the DPS Personal Animation Recorder and Sunrize's AD516 I know
half a dozen people with both the $$ nd the desire for the speed and storage
space that they give.
Non-linear video editing will create a LARGE demand for big, fast drives.
-Chas
First, Personal Animation Recorder records anims DIRECTLY to a DIRECTLY
ATTACHED ** IDE ** drive, I believe.
Second, Sunrize's nice AD516 board (which we have a couple of in house) can in
theory play back up to 8 individual channels of 48KHz audio at once (out of one
stereo out, mind you). Let's look at that data rate…
That's 48000 * 16 bits * 8 channels = 768000 bytes per second (750K).
Doesn't exactly require the 10 or 20 *megabytes* per second that SCSI II FAST
or SCSI II WIDE & FAST does it?
Non-linear editing is another story, but there are no real solutions for the
Amiga yet, although obviously there is likely to be down the road. The DPS
stuff is nice, but as I said, this uses a direct IDE interface and is seriously
compressed (JPEG'ed) data. Not criticizing mind you, it's a very nice product.
Regards,
Paul.
Well, that is sort of incorrect. Yes, it is a direct connect IDE drive, but it
is not a standard IDE drive….there is only one drive and one manufacturer
(Seagate). It is a VERY fast drive and compression rate is variable. I have
used it (and will again Saturday) with both piped in video (VHS copy of
Excalibur) and internally generated animation (Lightwave). There was no
difference between what the VCR showed and what the captured video showed.
There was no noticable compression artifacting (and I stepped through a minute
and a half of video frame-by-frame). There WAS some minor artifacting with ONE
of the animations I saw…and it was only visable when paused on those frames
(same object — a window out onto a red sky; tilted and looking through a
flagstone wall) and there was only ten frames of this.
Saturday I'm getting to try SVHS and 3/4" video in. (I discovered something
neat — Excalibur (and the other films I checked) were filmed at 24 fps. When
grabbed with the DPS at 30 fps, every third frame was a staggered field.
Neat.) Don't knock it for the IDE drive…it is a new form of IDE that stomps
normal SCSI and competes with SCSI-II WIDE (considering it is a custom
controller and has no contention with other devices).
Play with the DPS board before deciding anything. It is a VERY interesting
product hat CAN (read "is now") be used for cable-network broadcast output.
-Chas
Hi Chas. As I said – the DPS Animation Recorder is a very nice product.
Limiting it to one brand of hard drive however is a bit of a shame. I'm not
sure why they didn't just go SCSI, although that requires a lot more software.
As far as this special IDE drive 'stomping SCSI', I don't believe it. As
mentioned before, even plain ol' SCSI handles up to 5MB / second which 99% of
available drives cannot come close to spitting out off the media, especially
not sustained.
Plain old SCSI can do up to 5MB/second if you can eliminate the overhead
of SCSI your controller's command processing. With a sufficiently
expensive SCSI controller chip, no problem. With ordinary controller
chips usually found in an Amiga, HDs rated at the same speed but one with
IDE interface and one with SCSI, the IDE one will usually win — but there
might not be much CPU left if the IDE isn't DMA 🙂
Dale Larson
– An Amiga Software Engineer with lots of time on his hands.
Well, I'll run some speed tests. All I know is that this device was able to
capture, in real time hi-res, 24-bit; 30 seconds of Excalubur from a VHS drive
and compress it to a 90 Mb animation file…in real time.
Transferring files…it blows the door off my A1200 (IDE), A4000 (IDE), A3000
(SCSI) and A2500 (GVP Series II SCSI). It's more on par with my A3000's RAM
drive (about 10 Mb/s). Still, I'll see what SysInfo says about the drive
transfer rate.
-Chas
Hi Chas. It's not that simple. The DPS system has an LSI Logic compression
chip set on it. Those (roughly) 800K 24 bit full screen frames are probably
going down as 80K or so (10:1) on the drive. That makes it easy for the drive
to keep up.
But (I'll say it again to make sure there's no misunderstanding) it's a NICE
PRODUCT; I'm not criticizing. We're jealous at GVP <g>.
GVP jealous? Heck, you guys can't do *everything* 🙂
DPS makes some real nice stuff (TBCs, Waveform, etc.).
There is a noticable lag when copying compressed files from their drive to
other AmigaDOS devices.
-Chas
Paul,
Sorry….there is no consumer drive on the market that can sustain
rates of 5MB/sec.
Do the math. 3600rpm = 60 revs per second. Even at 35 sectors per
track, you can only read 35 x 60 sectors per second and at 512 bytes per
sector…that equals 35 x 60 x 512 or 1,075,200 bytes per second. You'd
have to have 5 times the number of sectors per track, 5 times the
rotational speed or be able to read 5 tracks at one time in order to get 5
Meg/second off of the media.
Burst mode, with buffered reads and/or buffered read-ahead and you can
do it…but sustained…not physically possible out of consumer drives.
Stripped disk arrays…yes, single drive…no.
Don
How about the Maxtor drive that does 4MB a second, sustained, on an
A3000… I can't remeber the model name, but I know it performs this
well.
So 5Mb probably isn't out of the question.
I believe it get its speed increase from the organization of data on the
drive, so that it can read more than one track at a time, i.e. it reads a
cylinder at a time.
Bob Comer — Cruising the nets on AutoPilot from Cheyenne, Wyoming
Robert,
As I've said…I've yet to see a *consumer* drive that can hit those
speeds. Yes, if the drive can do multi-head reads…it's quite possible,
but drives that do that are in the $10,000 price range on up.
Also, don't forget, read-ahead cache on the drive can give the
appearance of faster transfer rates. That is, the system asks for 100
sectors, the drive will read and pass on the 100 sectors, but it will also
read the next 100 sectors (or whatever it's set at) into it's on-drive
cache. IF the next request is for those sectors…they're already in the
cache and the transfer is at full bus speed since no physical access is
required.
Many drives also use intelligent caching for both reads and writes.
Again, like software drive buffers (cache) programs on the Amiga itself,
the drive itself maintains a similar cache (again…the more expensive.,
but still in the consumer category)…so for example…frequently read
data is likely to be in the cache and the transfer is extremely quick.
However, take any of those drives and end to end reads and you'll find
those numbers drop significantly to the true sustained read rate.
Don
I believe anyone can buy the Maxtor drive (MAJIK amybe?) I'll see if I
can dig up a price. I don't think its over 10,000, but I may be wrong, (I
never tried to buy one. I know this drive has been made awhile.)
Your definitely right about normal drives and cache's!
Maybe you can answer a qusetion for me that I haven't been able to fiure
out exactly: (my thoughts are that it's a bug in the scsi.device IDE code,
not allowing the drive to use it's cache somehow)
I have an A1200HD, 10M of RAM '881 FPU, with a Seagate 92144A 2.5 inch IDE
drive, 16ms access, internal transfer rate of 14.5Mbits. I'm getting a
rediculously low transfer rate on the drive, (197K/s on reads). Now here's
where it gets interesting :), If I do a SCSI Inquire through scsi.device
(which get's changed into an equiv IDE inquire?,) just before a series of
reads, the transfer rate goes up to 880-900K/s, but then it drops back
down to 197K/s on the next group of reads (without an Inquire before)
I get the same results with Diskspeed if I cheat and have another program
do the Inquire just before it does a read test.
Any Ideas?
Bob Comer — Cruising the nets on AutoPilot from Cheyenne, Wyoming
Thanks for the supporting info. We at GVP tend to keep up on these things, for
obvious reasons.
Parallel head drives do exist, but I'm not aware that Maxtor makes one.
Parallel head drives from Seagate (the only ones I am aware of) don't come with
SCSI interfaces however, only IPI. COOL drives, however. And of course,
HUUUGE $$$.
I believe the name of the drive is Maxtor MAGIK. It might not be parllel,
educated guess, because of its speed. If not parallel heads, how does
this drive work?
(The drive I'm talking about is SCSI)
At the last place I worked, we had some SCSI RAID drives, (hooked into an
AS/400, very impressive speeds! But definetly out of my price range 🙁
Bob Comer — Cruising the nets on AutoPilot from Cheyenne, Wyoming
Panther 0 – 3600rpm, 76 sectors per track, 15 heads.
535meg MAXTOR: 3600rpm, 61 sectors per track, 11 heads
Majik: 6300rpm, 85 sectors per track, 15 heads
These all well exceed the 1meg per second bogey.
{@_@}
Thanks Don, that supports my case even more that people don't need controllers
that brag about 5, 10, even 20 MB / second. They might be able to use SOME of
the bandwidth SOME of the time, but over the long haul it doesn't buy them
much.
Paul,
Exactly…a high speed bus is useful in some instances. For example,
if the system and drive support re-selection, the system can tell the
drive to read X number of sectors and then disconnect from the bus. The
drive can go read those sectors into a buffer…or at the least, seek to
the proper track and then return onto the bus and do the actual transfer.
If it's from a buffer, it can be quite quick, if it's from the drive, it
won't be as quick…but the bus will not be tied up quite as long.
Of course, this is only useful in systems where you've got multiple
drives and are attempting read/writes from multiple drives in the same
time period.
For general use, a 2 Meg/sec bus is more than adequate.
Don
Yup, yup. As I mentioned, we at GVP are fairly familiar with these issues <g>.
People have asked us a lot why we haven't come out with a SCSI-II Zorro III
controller for the A4000. Well besides the typical performance issues being
discussed here, one only has to look at the "Pandora's Box" of issues
surrounding the installation of an A4091 to see why we've been taking our time.
Because Commodore didn't build the A4091 when the A4000 was being developed
they didn't find out that the Buster was buggy (i.e., DMA on Zorro III doesn't
work). That's a pretty bad planning / testing situation I'd say.
I'm impatient.
{@_-}
You're ignoring the fact that many drives consist of stacked arrays of
disk heads and media. If you read the data from 4 or 8 heads at once,
you'll get that much of an increase in data thruput. It's an old trick.
Erik Flom
Erik,
No, that's why I said "consumer" drives. Drives that do multiple head
reads/writes are quite expensive. But yes, they're quite capable of
reaching those high speeds.
For example, a RAID 5 array can usually read a minimum of 11 heads at
once (spread over 11 drives)…that's 8 bits of data and 3 bits of error
correction information. Even more expansive arrays read even more heads
and, of course, correct even higher data bit errors.
Don
It would stand to reason that multi-head technology technology will begin
to become available to 'consumer level' drives in the near future.
And, while it's true that the average 1200 owner isn't going to need
SCSI-II, the higher thruput rate will only make our lives easier.
(Esp. if you want the Amiga to remain a viable contender in the only niche
market it has now: Video?)
Erik Flom
Bad numbers Don. Good math.
The fastest drives around are spinning at 6300rpm or so and have close to
100 sectors per track and something on the order of 15 heads. They
*SCREAM*. (The MAXTOR Magic has been clocked in my presence at 3.9megs per
second using diskspeed4 and when carefully "tuned" has gotten over 4megs
per second.)
{@_@}
Joanne,
I limited my discussion to "consumer" drives. For clarification, I
consider a consumer drive to be one that's in the $2,000 or less ballpark.
While I have no idea of the price of the Magic…I suspect it's not in this
range.
The number of headsis really of no concern in read speed discussions
unless the drive is capable ofreading more than one head at a time. The rpm
and sectors per track are of concern. A drive running at 6300 rpm is doing 105
rps. At 85 sectors per track (presuming they're 512 byte physical sectors)
that's equal to 4.36 Meg/Second max sustained rate. Close…but still short of
the 5 Meg/Second rate.
And, of course, that speed presumes 0 time to switch heads or step to
another track. If the sectors are properly laid out in a cylinder, the head
switch time can be essentially 0. But the step rate can be 'significant'.
Taking your Magic drive at 6300 rpm/85 sectors per track/15 heads and
presuming a 0 head to head switch time, but a 10ms track to track step/settle
and find sector 0 time…in order to read 5 meg, it must read 10,240 sectors.
Your drive has 1275 sectors/cylinder. So the 5 meg is contained in slightly
more than 8 cylinders. That's at least 8 track to track steps required or 80ms
added to the actual read time.
Since your drive reads 8925 sectors per second (105 x 85) the actual
read time for 10240 sectors is 1.147 seconds. Add the 80ms step time and it
will take 1.227 seconds to read the 5 meg presuming it's laid out properly. And
that is an effective rate of 4.075 Meg/Second…about 20% short of 5 meg per
second.
Don
Paul, I am GLAD I am not the only one saying this. I've been arguing about
this over on BIX as well. There simply no IDE drive that can approach the
transfer rates of typical SCSI drives in the 1.3 to 4 gigabyte size range.
And on a well written system there is precious little overhead difference
between SCSI and IDE. (At the level of 500meg drives, such as they use, it
is barely noticeable if the drive is used efficiently. If it is used with
small transfer commands then it can be faster, though.)
{@_@}
Surprise surprise…. I thought that I would be able to use a very nice scsi
array that we have at the office, with the DPS par board, but guess what….
The PAR board apparently only accepts IDE drives!!! My dealer told me this
yesterday when I called to find out if it was in or not. Although I can't
afford to buy one of my own, the array is very nice.
So far the biggest ide drive I can find (that is shipping) is 512 megs….
🙁 Bummer….
I can get you 1.05 gig IDE's…they are $1200.
Dave
Elite MicroComputers – Flying high on AutoPilot
It is not standard IDE, but a new form that is very fast. They are in short
supply and only in 512Mb right now. Seagate is expecting to have a 1 Gb out by
September and larger by end-of-year.
512 Mb is about 6 minutes. VERY nice for commercials, and with a DAT tape
drive it could be made to work with 1/2 hour programs.
-Chas
Well, I finally got the board and needless to say I am not happy to have to
wait for one of the seagate drives. My boss wouldn't let me take one from the
file server (wonder why). I also went ahead and ordered the tbc IV card, and I
was not happy to have to do that either. So I have gone from a reasonably
priced solution to one that keeps growing by the minute, and has turned into a
300 lb gorilla…
On top of that I'm still waiting for toaster 4000 and my wife is considering
leaving me….. 🙂
Well, my situation is a bit different. I knew the drive and TBC-IV were extra
and needed but the cost was still way under what I was paying for a 3/4" edit
suite (rental).
Word is that the Seagate drive is in short supply. I would have preferred a
SCSI-II controller instead of a new-fangled IDE, but I wasn't asked about it
🙂
Let me know how it goes (when you get the drive). I'm pleased simply because I
can do real editing at home. I've started dumping my bosses SVHS footage onto
the drive and backing it up to DAT tapes. We're just looking at creating a
digital library right now.
Sound is next. I'm going to see about trying to sync the AD-516 and the DPS
PAR to do real audio/video grabs simultaneously as well as proper editing of
both.
-Chas
Charles,
that will be nice (ad516 and PAR), I would be interested to know how it works
out for you. I have been told that I will get my drive in a week or two. It
seems seagate wasn't ready for this "sudden" demand.
How's the quality of those segments you have processed ? Any noticable
degrading of the signal ?
Considering 1) The source quality that I am using (internally generated anims;
SVHS, Hi-8 or 3/4" video) and the ustimate destination of all my output (VHS
tapes), no there is no noticable degredation.
I've yet to try 3/4" to 3/4" so don't know if there is any signal dropoff.
-Chas
You don't really understand a sizable portion of the Amiga market. HUGE $$
is only relative. BIG servers indeed! Home use I say!
–Paul < Motorola Inside >
Hi Paul. I am certainly aware that many home users spend a lot of money on
Amiga products, but SCSI II fast and wide drives are really not available,
i.e., you can't really buy them unless you know someone. But I am curious,
what would you use a, say, 2.2GB drive with sustained 5MB/second transfer rates
for at home? Since the drive will cost more than the rest of the entire
system, it might make more sense to think about just buying a workstation.
A worksation would not be a wise idea, they are cheap enough, it's the
price of the software that would kill me. I have a AD516 and AD1012 that
really loves to suck up harddrive space in a hurry. I work in 40 minute
blocks at a time.
My faithful Video Toaster cranks out animations 600 frames at a time. I
then need to make a modified version of each frame in a post op type
function. One little animation uses up 715 megs of data just for the pics.
The sound bytes add up to about 380 megs of working room.
Since I do have the luxury of a 68040 I also get it's curse which lets me
do multiple variations on a theme, and I find it difficult to hit the
delete button on a nice fat 20 meg animation. Even if it was "just a
test".
Moving mega-chunks of data off a harddrive quickly is critical for doing
evaluations with DCTV and big delta moves. This is to go live off the
drive straight onto tape. No single-framing here, just brute force and
speed. My little 426 meg SCSI II drive can barely keep up.
I am not alone.
–Paul < Motorola Inside >
Paul,
You may want to consider a DAT tape drive over 1 Gb and TapeWorm FS from
Moonlighter Software. TapeWorm allows the drive to look like any other
AmigaDOS device: you can read, write, copy, etc. to/from it like a disk drive.
Granted, you don't want to try playing an animation from a tape drive, DAT or
not, it is GREAT for rendering them big anims to. Save yourself drive space
with all them animation frames. Archive EVERYTHING to the drive (audio, video,
files, etc.) without any special software (though AmiBack w/AmiSched is very
nice 🙂
-Chas e/xit
This is an unexplored option, thanks for bringing it up. Do you know how
long it would take to get to the end of the tape.
–Paul < Motorola Inside >
Well, that depends on the length of the DAT tape. My understanding of tape
drives (which is limited) is that NORMAL drives have a header section (or maybe
a footer) where the directory information is stored. So…everytime you want
to access a file, the tape has to be wound/rewound to that section to read the
directory. Ugh!
With DAT tape, there is a track throughout the entire tape (like an audio track
on a video tape) that contains directory information…OR…. A DAT may just be
@^%#$ fast because it is digital and have to use the analog method of "am I
there yet…read tape section…am I there yet…etc." of finding the
directory.
DAT drives are more expensive than normal drives (a good DAT will run you
$1,000 new, or $500+ refurbished). They are much faster. I'll ask Gary at
Moonlighter about the DAT methods and speed — they also sell tape drives
(Archive Vipers and new/refurb DATs).
-Chas
DATs have a partition at the begining of the tape where the dir
information is written. Once it reads the partition info and puts the dir
info in to memory it then knows where EVERYTHING on the tape is. Thats why
they are so fast at retreival. To my knowledge, all other normal drives
(including 8mm exabytes) just throw the crap on the tape. Once it is there
either the back-up software makes a list file or the tape has to be reread
to find out what is on it. ANSI and IBM labeled tapes (this is a form of
writing, it has nothing to do with the drive) write header info before
each file.
Dave
Elite MicroComputers – Flying high on AutoPilot
Chas,
DAT tapes use the same helical scan technology that VCRs use, although
improved for reliability. As a result, they can pack a significant amount
of data into a small area and the head-to-tape speeds are quite high..even
though the tape speed (ips) is relatively slow. And, of course, with the
high head-to-tape speed, they can also write a lot of data quickly.
As to where directory or file information is kept….that's a function
of the backup program. The drives themselves are streaming devices…that
is you just "pour" the data into them and they store whatever it is you
sent them. If you wrote a filesystem onto the tape…yes, that can cause
significant slow-downs as it would have to find a directory sector(s)
every time you wanted to read a file.
The backup systems I'm familiar with (the software portion) simply put
a header on each file that contains the file path and other necessary
information (such as file size, ownership, filedate, last access date,
etc.). There's usually an end-of-file marker also so that if one file is
corrupt, the software can seek to the EOF and then look for the next
valid file header. To recover a file from the tape, the software simply
reads the tape until it finds the correct header and then does the
recovery. If you're recovering multiple files…the software just looks
for any one of the filenames as it reads the tape..and recovers files as
it locates them. That avoids the 'find one file, rewind, find the next
file, rewind, etc.' scenario.
Don
Thanks for the update Chas, I didn't know Gary also had DAT refurbs. Do
you remember how much? This is starting to sound much better. I already
have one of his Vipers.
–Paul < Motorola Inside >
No, I can't remember the price, but heck…Moonlighter is within walking
distance from my house. I bug those guys regularly…I'll ask.
-Chas
I know a guy who works for a company that gets Seagate OEM and betas.
I has a couple of the new 3.5gigs. Sez they are the fastest drive he
has ever used. They use some kind of new head technique…I dunno
working with harddrives is his life so he kinda went over my head
when explaining it. But he did mention this is the last step, till
seagate goes with some kind of liquid filled drive scheme. Supposed
to hit like 10,000 RPM <g>
<snarf> <choke> <gasp> Seacrate? Have they really learned you cannot
cheapen up the old Wren designs (er "value engineer them") and keep them
running reliably? I heard they had some HORRRRRRID problems after trying
to use a cheaper head assembly for one.
So far I have liked Micropolis best. Their ultrafast drive has some nice
special SCSI control codes to facilitate live video capture to disk at
astounding data rates.
{@_@}
Joanne – great to "see" you! Re: Seagate, we've certainly been unimpressed
until recently. Can you tell me what Micropolis models are really fast?
Thanks, Paul.
OK, then two questions:
1. Is the "GVP Series II HC8" the same as the board that is called
"GVP SERIES II A2000 Hard-Disk+RAM-Card" on your box labelling?
2. Will it work in the Amiga 4000?
–apl
1. Yes (we're trying to get rid of references to A2000 since it works on A4000
also).
2. (Therefore) Yes, it works fine in an A4000, as long as it has the version
4.13 ROM, I believe.
Paul.
Paul,
a friend of mine with an A500+ and an external SCSI drive needs just an
inexpensive SCSI controller for connecting the drive. Does GVP manufacture
such a thing ?
Regards, J0RGEN ….from DENMARK
I believe we mainly offer our A500HD8+ with a drive in it, but I think we do
also offer it without. The A500HD8+ is nice because the case work EXACTLY
matches the A500, you get internal and external SCSI connections and two SIMM
sockets for up to 8MB (16 bit) RAM. Your friend should check with his or her
friendly local dealer. We do have a distributor in Denmark.
Thanks for your interest
Paul.
Yes, I have seen ads from Danish dealers for the HD8, but always with disk
drive included. However, one important information you provided was the
fact, that it includes an external SCSI connection. I'll get on the phone
to the dealers.
Regards, J0RGEN ….from DENMARK
Very good information… and very nice to hear that the Series II SCSI card
will work with the A4000. I'm surprised you guys haven't pushed/advertised this
heavily — I expect many A4000 buyers/potential buyers would have been VERY
interested in getting a SCSI board instead of waiting for 4091 or kluging the
2091.
So another question: I have one of your Series II cards in my A2000,but it is
about two years old so it most likely doesn't have the 4.13 ROM. What is your
policy/cost in getting the upgrade? I am considering moving to an A4000 and
being able to use my Series II SCSI is what I want.
Oh, and will the additional RAM on the Series II card also work properly in the
A4000?
P.S. My GVP Series II card (w/49MB Quantum and 2M RAM) has worked well for two
years — good product. –apl
>I'd like to try and hopefully straighten out a few misconceptions about
>SCSI.
Paul, I LOVE YOU!!! Thank you for posting that very important
revelation. I have been looking into getting a bigger SCSI drive and
thought I understood SCSI II but I was wrong, thanks again.
<<< Tony D. Tracer >>>
> Paul, I LOVE YOU!!!
Wow <blush> – now that's what I call gratitude. We, er, care deeply about
Amiga users also.
> Thank you for posting that very important revelation.
Just trying to be of service because I saw people getting it wrong over and
over. Some people WILL need SCSI II FAST or WIDE, but most won't.
Regards,
Paul.
Thanks Paul, that helped a lot with the SCSI-I/II confusion. I guess I
will find out sooner or later whether or not the 4091 can live up to it's
expectations. I just purchased a 1.23 GB SCSI-II 9ms drive so as soon as I
can get my Buster chip replaced then I will do some testing and post the
results.
// John – (Flying via AutoPilot)
\X/ "Worf: To Hell with the Prime Directive – Give the Borg Windows!"
Well that sounds like a great drive, so I'm sure you probably will see better
performance on the 4091. Enjoy!
Paul.