#BE CAREFUL WITH WEITEK!
15 messages in this thread
Folks: I just found out today that the combination of a Weitek 4167-33 and
an IceCap running in a 50 MHz 468 system ***DOES NOT*** always run
properly. Although this has been recommended as a way to get a Weitek on a
50 MHz system, Weitek no longer seems to see this as a viable way to go.
They say that initially this looked good but with experience there have
been a number of people having problems with this setup.
Unfortunately, I've joined that club as of today. My Weitek almost works,
seeming to work normally on their fractal and shaded ball demos but failing
a number of the tests in the 67diag set.
It seems that, while all of the 4167-33s will work at 33 MHz, not all will
work at 50 MHz even with the IceCap. I've heard of somebody selling Weitek
33s that have been tested and found to work at 50 MHz with an IceCap, but I
haven't run the lead down yet.
More when I get it…
Chris
Chris,
Big news. I've been telling people that for 5 months, including on
the forum. Sorry you got stuck anyway. In fact, I had to tell Weitek.
Call Henri DeRoule @ Ice Cap Technologies (formerly Velox) @ 408/727-6100.
Either they will try to get a proper thermo-bond of the Ice Cap to the
Weitek (and test the combo before returning to you), or Weitek will take
the chip back (same for Ice Cap on their unit). You might even try to get
them to select a chip from a Weitek run (try Joe Laird @ Weitek tech
support).
Or, how many do you want, and what are you willing to pay?
Kevin Krell – Computer Support Associates
Kevin,
I just ordered an AST 486 50 MHz with a Weitek 4167. I believe that the AST
is really a 25 doubleed. I don't know what Ice Cap is but this message
thread alarmed me. What is Ice Cap? and do you know if I can expect the
Weitek to run well on a 25 MHz doubler?
With Panic, Chris Barnes.
Chris,
Don't Panic. A 486/50DX2 (doubled 25MHz chip) runs at 25MHz outside
the cpu chip. Thus, the Weitek you'd use is a 25MHz model – no problem in
this instance. BTW, the Weitek 4167-25 is real cheap now – Weitek dropped
prices on all processors (significantly) except for the 33Mhz model.
Kevin Krell – Computer Support Associates
Whew! I'm still new to the animation world and the variety of hardware
available and the miscellaneous compatability problems boggle my mind.
Thanks for your input!
Chris Barnes
Kevin: Well, **I** didn't see your warnings about the Weitek/IceCap
combinations! <g> Actually, I had to wait a while for the computer so I had
the Weitek and IceCap sitting in my filing cabinet until this week. I
bought the combination based on the original stories about the combination
(and, in fact, Weitek told me that they were considering whether to build a
50 MHz chip or just use IceCapped 33's. I figured that, since I had not
seen anything about the problems here, I should let people know of my
experience.
Thanks for the tips, and the names. I'll give them a try and see what
happens. Unfortunately, I only need one.
Chris
Well, my Weitek/33 works fine on my 486DX2/66. Really lets 3DS fly!
So you are using the Ice Cap with the 66Mhz? And no problems?
-MM
Mike,
The Weitek 4167-33 is running at its rated speed (33MHz) in the
DX2/66 (33MHz external to cpu, 66MHz internal on the 486/DX2 chip).
Kevin Krell – Computer Support Associates
No ice cap, just the Weitek. The bus is only running at 33MHZ, so there
sould be no need for anything else. At least that's the way I THINK it is.
(so indecisive…)
Sure, your 33 MHz Weitek would, since the DX2 is the clock doubled chip and
the outside world sees it running at 33 MHz.
I would be interested in somebody comparing rendering times between the
internal coprocessor and an external Weitek on a 25/50 MHz DX2 system.
Since the Weitek is rumored to give a 2X performance increase over the
internal coprocessor, you would think that the rendering times might be
pretty close, considering that the Weitek would run at 25 MHz and the
internal coprocessor at 50 MHz.
Chris
Ok, here you go. I rendered the ADBLOCK.3DS file, RCPADI on a standard
TSENG ET4000 chipset, Phong/Low and all defaults. It took 53 seconds.
(1:31 on my 486/33)
Hardware: 486/DX2/66, Weitek, 32MB Ram (only used around 6 for this render
I think), 3DS RII, etc.
Hope that helps. Ohh yeah, I rendered to my standard RCPADI 640X480X8bit.
Who's shipping the 486/66?
Steve Ormonde
We just have a model in here for testing. It's a TTC board.