Among the DIMM modules I found one pair of 32MB modules with EDO DRAM chips that fitted to SIMM modules. I was surprised (I thought DIMMs were already fitted with SDRAM chips) and would like to know where they were used?
Thank you for explaining.
Quite a few boards with chipsets compatible with both types of RAM can use EDO DIMMs. Many 440lx/bx boards for example.
I had old HX motherboards with dimm slots
PPRO would many times also have dimm slots.
In both cases the chipset required EDO/FPM
Want some real fun?
FPM existed in dimm form and dimms of that period could be 5v or 3.3 volt so you had to make sure your mobo could set voltage correctly and don’t mix voltages.
There was even 5v and 5volt tolerant SDRAM in the early times, much of which wasn’t JDEC compliant, making timing and compatibility a nightmare .
Intel wisely kept SDRAM support off their high end offerings until quite late in the game due to poor standardization of SDRAM, especially pc100, during this time many stuck with old reliable EDO Dimms to avoid the nightmare of sourcing sdram that would be stable with their system.
Beyond x86 there was all sorts of crapola that used dimms before SDRAM was common, even Macintosh.
In the day what sucked was 32mb of “dimm” memory was twice the price of 32mb of Simms , that incomprehensible cash grab went on longer than you would want.
Recently came across some similar myself in a job lot I bought , remind me of the 0.5mb ram chips I used back in the day on my old Spackard Bell P100 to upgrade the onboard Cirrus Logic graphics to a whole 2mb 😂
Build 1
Win98se
Dell Dimension XPS B866r
1.0ghz PIII
512mb 800mhz Rdram
Asus GF2 Ti 64mb
Build 2
XP System
Lian Li PC65 USB
Athlon 64 x2 4800+
Asus A8N SLI Premium
2gb Corsair XMS 2
Asus 6600GT 256mb
Thank you all for your answers.
Doornkaat wrote on 2021-09-18, 12:36:Quite a few boards with chipsets compatible with both types of RAM can use EDO DIMMs. Many 440lx/bx boards for example.
But aren't EDO DRAMs slower than SDRAMs? So what would be the reason for the use - were SDRAMs more expensive than EDOs? I don't rember that time, that's why I ask.
rmay635703 wrote on 2021-09-18, 12:59:Want some real fun?
FPM existed in dimm form and dimms of that period could be 5v or 3.3 volt so you had to make sure your mobo could set voltage correctly and don’t mix voltages.
There was even 5v and 5volt tolerant SDRAM in the early times, much of which wasn’t JDEC compliant, making timing and compatibility a nightmare .
Yes, I know. I have jumper for 3,3V/5V selection for DIMM on mine PCChips M590:
Yes, I believe it was mostly a cost thing. Also DIMMs gave you the 64bit bus width that was required for S5 and up on a single module so you'd only need one stick of RAM which is a bit more convenient.
