The VX chipset is picky about what SDRAM it will work with. My PCChips M520 does have jumpers to change the memory voltage when going from SIMM to DIMM, but I had a look at the manual for your board and there is no mention of any jumper change needed , and on this board you can even use SIMMs and DIMMs at the same time though I'd think your best option would be to only use one or the other.

Because of memory address limits of the VX chipset most commonly available SDRAM won't be detected properly. Joseph Joestar mentioned that he had good luck with memory modules that were only partially detected on his VX chipset motherboard, I.E. when using a 256 megabyte module only 64 megabytes were detected. I gave that a try with my M520 and I was finally able to get it to POST and detect the RAM with a 256 that was detected as 64 megs, but there was some other issue because it wouldn't successfully boot into Win98. But you have a better quality motherboard so you have a better chance of making SDRAM work.

One thing to keep in mind is that this is a very old motherboard and there is a good chance that the SDRAM slots have never been used prior to this. Repeatedly inserting and removing the RAM from the slots might help if the contacts have become oxidized, but contact cleaner may be necessary. Definitely stick with dual sided SDRAM modules.

From the old Wim's BIOS FAQ. https://web.archive.org/web/20060209035056/ht … w.wimsbios.com/

This thread is relevant, and this post may explain why I had no luck with SDRAM in my M520. Re: Help with 32MB SDRAM Selection for ECS P5VX-A VER 1.0

Thank you so much yes i never thought about the contacts... the board is filthy so chances are it needs a good clean

That said, is there much performance to be gained going from EDO to SD ram realistically?

Crinale0 wrote on 2024-08-27, 17:36:

Thank you so much yes i never thought about the contacts... the board is filthy so chances are it needs a good clean

That said, is there much performance to be gained going from EDO to SD ram realistically?

On A first generation pentium SDRAM chipset
nope, it was an overused novelty until SDRAM faster than 66mhz FSB became common.

Pentium Pro+ with the deep pipeline actually did gain a lot from sdram.

On a VX motherboard if you can find good EDO you are loosing under 5% of potential performance, only exception would be if your overclocking the FSB to 83mhz and even then…

Crinale0 wrote on 2024-08-27, 17:36:

Thank you so much yes i never thought about the contacts... the board is filthy so chances are it needs a good clean

That said, is there much performance to be gained going from EDO to SD ram realistically?

It isn't huge, but it is there. It can really come into play when you use something like a K6-3 and a higher than 66 MHz FSB.

Intel 430VX Triton II SIMM vs DIMM performance

Sdram will start to shine with 430TX and later chipsets.

For VX chipsets is usually very frustrating finding modules that most boards can accept.

All that is said here is correct

However I had many problems with early Pentium motherboards accepting the SDram modules but it all was only related to bad contacts
After flooding the slots with contact cleaner and reseating the ram many times, sometimes the board would start working

incompatible ram module - 70% probablitly
dirty or bad contacts - 30% probabilty