CompuServe Thread

#Speeds of RAM?

5 messages in this thread
#63954From: Tim CarterJul 28, 1992 1:25 AM
I own a 3000 Tower. I want to expand its RAM to 18MB. Would there be any problems in using 80ns 256Kx4 Static Column ZIPs for the Chip RAM and 70ns 1Mx4 Static Column ZIPs for the Fast RAM? In other words, will mixing the speeds of the Chip and Fast RAM have any detrimental effects on the Amiga? Thanks.
#63956From: OCO-IM/BSJul 28, 1992 2:37 AM
Careful, you cannot use ZIPs for Chip RAM; on the stock A3000, there's 1MB Chip RAM in separate sockets with space for one more meg. The Fast RAM section comes with four banks for ZIPs, expandable to either 4MB or 16MB, depending on which ZIPs you choose (but you cannot mix the two types at all). Also, below the Fast RAM sockets, there is a row of chips, 1MB, your stock Fast RAM memory. These chips are addressed as bank 1 of the Fast RAM section and have to be moved when you add ZIPs for Fast RAM. Where do they go? Into the empty sockets for Chip RAM, to give you 2MB of it. So, no ZIPs for Chip RAM, and you have to move the stock Fast RAM into the Chip RAM sockets when you add ZIPs for Fast RAM. Mixing speeds shouldn't matter as long as your chips are fast enough. How fast they have to be is in the manual. How do I know? I've been through the entire thing two weeks ago when I added 8MB Fast RAM to my A3000. Cheers, Nikolaj
#63999From: Tim CarterJul 28, 1992 5:25 PM
Nikolaj, The 3000T's RAM configurations are different than the regular 3000. For example you cannot use 256Kx4 ZIPs in the Fast RAM section. The Chip RAM *does* use ZIPs in the Tower, I just wasn't sure if it was OK to mix the speed of the chips.
#64036From: OCO-IM/BSJul 29, 1992 4:37 AM
Talk about poor assumptions… Well, I learned something new then. Cheers, Nikolaj
#64207From: Patrick DohertyJul 31, 1992 1:39 PM
I have an A3000 (no tower) with 70 & 80ns speed chips mixed in the Fast Ram section and am not having any problems. 1×4-80 SC Zips and 1×4-70 SC Zips. Patrick