I have four sticks that seem to be 1MB each but when I put all four in my 386 16MHz it shows up as 5MB, if I put each stick in one at a time they show as 1MB. Im using AIDA10 and AIDA16 I thought it was a problem with AIDA but all 4 sticks in show as 5MB on boot after memory checking
HM514400A/AL/ASL series
1048576-word x4 bit dynamic ram.
you've got 4 modules of 1Megabyte & 1 bit parity (supplied by the HM511000AJP7) with a 70ns access time.
you say you are testing on a 386 16MHz. Which mainboard exactly, and is it SX or DX ?
386SX would require two sticks to get 16 bits, and 386DX would require all four sticks to get the 32bits for the memory bus.
you say you get 1MB with only one stick installed. This would lead most people here to suspect that your mainboard incorporates 1MB of RAM onboard.
This in turn would lead to the normal 5MB of ram installed when you install all four memory modules on your board. ie four times 1megabyte of ram in the modules and 1megabyte of ram on your motherboard.
Right to repair is fundamental. You own it, you're allowed to fix it.
How To Ask Questions The Smart Way
Do not ask Why !
https://www.vogonswiki.com/index.php/Serial_port
Indeed. It seems there is already 1MB onboard - probably in chips. So with all four installed you get 5MB. Everything is OK 😉
Requests are also possible... /msg kixs
32-pin SIMM? You are definitely not alone trying to figure out their purposes: 32-pin SIMMs
I'm really surprised to see your computer can POST with those 32-pin SIMM.
Pin 1 and 32 are simply unused
imi wrote on 2022-07-14, 09:46:Pin 1 and 32 are simply unused
Is there any pinout or documents (e.g. technical sheets) explaining the purpose of those two unused pins? I've tried many times but just can't find any.
I have no idea, also in the other thread there's some with traces going off those pins pictured
It is the SX 386, before posting this I had seen chips on the motherboard but I thought they were cache somehow but unfortunately I cant find a brand/model number to look for a motherboard manual but it does have "A10001 Rev.B"
Nice board. And those chips are memory. 386SX boards usually didn't have any cache.
More info here:
https://www.ultimateretro.net/en/motherboards/5289
Requests are also possible... /msg kixs
The 8 bigger chips are GM71C4256A-80, a 256k words of 4 bit wide, 80 ns, that's your onboard 1MB of dynamic ram.
The smaller HY53C256LS-80 is 256k words of 1 bit wide, 80ns. This is the parity bits, one HY53 chip per pair of GM71C4256.
Effectively that's exactly the same as 4 slots of 256KB SIMMs, and there are SIMM modules built with exactly same chips.
kixs wrote on 2022-07-14, 11:28:Nice board. And those chips are memory. 386SX boards usually didn't have any cache.
More info here:
https://www.ultimateretro.net/en/motherboards/5289
a few 386SX boards had some cache built into the chipset iirc.
There were some chipsets but aren't that common.
Check here:
https://www.vogonswiki.com/index.php/386_Chipsets
Requests are also possible... /msg kixs
kixs wrote on 2022-07-14, 11:28:Nice board. And those chips are memory. 386SX boards usually didn't have any cache.
It's up for sale if anyone's interested 😁
