• Please review our updated Terms and Rules here

Can a PS/2 486 use a 32-bit MCA memory board?

If you have a 32 BIT slot then you can use the adapter, but I think the speed of the RAM on a 486 DX will be slower then motherboard RAM. I guess you have to decide if more RAM is needed even if it is slower then the built in RAM.
 
Unknown_K said:
If you have a 32 BIT slot then you can use the adapter, but I think the speed of the RAM on a 486 DX will be slower then motherboard RAM. I guess you have to decide if more RAM is needed even if it is slower then the built in RAM.
Click to expand...

Yeah, most likely they'll be at least a cycle delay in getting to the expansion bus, but quantity is more important than speed for some experiments I'd like to try.
 
southbird said:
Example: http://cgi.ebay.com/Kingston-KTM-30...156?pt=LH_DefaultDomain_0&hash=item2c571d031c

I'm seeing a few 32-bit MCA memory boards on eBay and I'm wondering if I can use them to extend a PS/2 76 I have. I typically only see these employed in a 386, and I suppose they were highly desired there, but I'm interested in pushing the limits on my 486... so was wondering if anyone tried this and if it worked or not.
Click to expand...

Is your 76 based on the Bermuda or Lacuna planar? For both models they were designed to have the maximum system capacity of RAM on the planar itself. Bermudas will be limited to 32Mb of RAM (4 x 8Mb modules), Lacunas go up to 64Mb (4 x 16Mb modules).
 
Pretty sure it's a Bermuda. Planar's up to 28MB (8 + 8 + 8 + 4) although I do have another chip on the way that should at least hit the max 32MB. Wouldn't happen to know what happens if you even try to get up towards even 64MB? I mean, the 386s apparently could support up to 64MB though it wasn't on the planar.
 
southbird said:
Pretty sure it's a Bermuda. Planar's up to 28MB (8 + 8 + 8 + 4) although I do have another chip on the way that should at least hit the max 32MB. Wouldn't happen to know what happens if you even try to get up towards even 64MB? I mean, the 386s apparently could support up to 64MB though it wasn't on the planar.
Click to expand...

The topic did come up on CSIPH in 2001 specifically for Bermuda-based systems (http://groups.google.com/group/comp...192dc/1b4aa62d7aa45aa3?hl=en#1b4aa62d7aa45aa3), but wasn't answered empirically either way...

I've not heard of anyone trying, but Louis Ohland typically attempts everything on the different models, and reports if he gains some ground...

But I don't see anything about it on his pages...
 
FYI, I obtained a Kingston KTM 64/8 Memory Expansion Adapter to play with. In my 76, with 32MB onboard, I tried a series of old "standard" 72 pin chips I had lying around; none increased the system memory, but usually triggered 162 and 201 error codes. I then tried a 4MB and 8MB chip I had previously used in this machine (i.e. PS/2 style 72 pin memory); the 4MB caused the system memory to count to 32MB and then "jump" to 36MB. (It looks odd, but I don't know if that's a side effect of the memory board or what?) After a configuration, it didn't complain anymore, MSD reported 36MB. The 8MB chip however just caused the 201. That's all I got for now..
 
You must log in or register to reply here.
Back
Top