4mb 30 pin edo desktop sims (need 16mb total)

[limboy777]

Hi I have an amstrad 386 sx25 with a limit of 16mb max ram. It currently has 8mb ram on two slots (2 X 4mb) used out of 4. I am looking for 4mb modules that will be compatible. Any help much appreciated.


Can anyone help with this question also;

Can i mix memory brand types i.e at the moment I have 2 X 4mb sticks (NEC). Can I add 2 X 4mb of another make or do they have to match exactly.

 

[dorkbert]

For 386sx time frame, you probably want FPM SIMMs.
I don't think they even made EDOs in 30 pin form factor; this is not to say that they don't exist, but I think EDO were predominately available in 72 pin form factor and less commonly 168 pin DIMM.

Mix matching could work, but were also a source of problem for some. It's safer to get match sets.

 

[Druid6900]

I'm pretty sure the computer can't read the writing on the memory, so, rule of thumb is that as long as the chip count and speed of the RAM are the same, you can use any old combination, and I have, successfully.

Dorkbert is correct in stating that the SIMMs are Fast Page Mode. I've never come across any 30 pin SIMMs that were otherwise.

 

[Le_Bear]

EDO 2mb

EDO 2mb

I recall struggling to acquire EDO as they were quickly fading out of sight. Some were even on sale! I recall passing by a sale shelf at a (circuit city maybe?) as i was heading towards the counter with my newly found 16mb edo chips @ $100 each. There was a sale shelf with some 2MB chips @ $2. I'm thinking, cool! I'll grab that too( I've got several of those at home, but who knows, this seems like a bargain). When I get to the counter with my $100 16MB, and the $2 2MB, the thing rings up like $300! The cashier goes all the way to the top office, yep! Those 2MB chips are still $189 bux! As I was driving home I finally realized, why hadn't I offered to sell them a few! (i'd like to think i still have a few of those ones around here somewhere)

 

[twolazy]

Some of the 386sx's require parity ram, really depends who made the mainboard. I have a bunch of 4mb 30pins , and a few 16mbs if you still need a few ... PM me with what kind you need too, like 4x3 or will 8/9 chip work, does it have to be parity, speed, etc ... I'll let you know if I have anything, and give pictures etc

While back I bought out a few stores entire stock of 30/72 pin ram. Had a huge amount of simms. Still have some, just not nearly as many. Alot of them are new still.

 

[limboy777]

Hi thanks to everyone for replying. You are right it is not EDO simms that I need, they are 4mb 30 pin simms although I dont know exactly what. I currently own an Amstrad Mega PC which came with a 486 SX 25 processor and 1mb RAM as standard however mine was upgraded to 8mb using 2 4mb simms. The other two slots are free and I know the maximum memory is 16mb.

I will try and post a link to some pictures of my current RAM which hopefully someone can identify.

 

[limboy777]

I was meant to write 386 SX 25. Cant seem to edit last post.

 

[Druid6900]

Hi thanks to everyone for replying. You are right it is not EDO simms that I need, they are 4mb 30 pin simms although I dont know exactly what. I currently own an Amstrad Mega PC which came with a 486 SX 25 processor and 1mb RAM as standard however mine was upgraded to 8mb using 2 4mb simms. The other two slots are free and I know the maximum memory is 16mb.

I will try and post a link to some pictures of my current RAM which hopefully someone can identify.

It is most probable that you need FPM (Fast Page Mode) SIMMs and most 30 pin memory was FPM.

The unusual thing is that it works with just 2 SIMMs installed as most boards required them to be installed in sets of 4.

 

[Stone]

The unusual thing is that it works with just 2 SIMMs installed as most boards required them to be installed in sets of 4.

Not at all... 386SX is 16-bit, like a 286, and unlike a 32-bit 386DX so its memory banks consist of two simms per bank.