appiah4 wrote on 2020-10-06, 13:59:

I have a bunch of high density (128/256/512MB) SDRAM sticks that I don't know whether they work or not. They obviously don't work in the motherboards I have, but they all appear to have issues with high density RAM sticks. Some boards detect some of them as half size, and some never POST with some them. I was wondering what kind of motherboard is a good choice for testing larger SDRAM modules?

A relatively more recent board with SDRAM support and support for the higher density modules that your current testing boards seem to have troubles with.
Boards with the most recent SDRAM compatible chipsets should have what you are looking for.

I used some sA board with a KT133A chipset, lacking an AGP port, for testing my SDRAM modules (without AGP I deemed it expendable), but I also used an older board for testing some of my older modules (most noticably the PC-66 32MB/16MB ones).

Which boards have you used for testing your SDRAM modules? Which SDRAM modules are you testing? Your question is awfully vague. Even terms like "high density" are all relative in the end and interpretation can differ.

Generally speaking higher density modules are more recent, so more recent motherboards should be more compatible with those.

If the memory module works with half its memory recognized, chances are pretty good that the module is functional, but the board can't properly handle it.
If the board will not even POST with one, clean the contacts (I use rubbing alcohol and paper tissues).

"High density" is the sort of term to avoid. What is "high density" today is "low density" tomorrow. Get into the habit of finding the exact chip densities of the DIMMs instead. That 512MB DIMM inevitably uses 256Mb chips, the rest could be 64, 128 or 256Mb. All of those were "high density" at some time, but certainly by the time 512MB DIMMs came along, every 128MB DIMM will have been classed as "low density"

As for which board to use - go for a Via PC133 controller. That gives you best compatibility (including oddball things like BEDO, VC-SDRAM and 16Mx4/32Mx4 chips) and flexibility in clocking.

Well, the board in question that I am using now is a VIA PLE133T Socket 370 and it is VERY picky about RAM, it does not seem to be just about how many Mb the chips are, but even their configuration - ie the wordsxwidth where the width appears to be critical as well.

Maybe an early Athlon board is a better idea?

If you purely want a board to test SDRAM modules with, you will want a board which has the best compatibility with any stick that was made as SDRAM module.
My guess would be a KT133A chipset as these were one of the most recent and, as Dion has already mentioned, also has compatibility with for instance VC-SDRAM.
Which exact board (or boards) you pick depends on which board you will end up wanting to use for the purpose.

However, I have noticed that the VIA chipsets of the era can be picky about RAM, especially if one starts mixing different types of RAM (different densities, different sizes, different manufacturers and different timings, etc). This is why I've always tested SDRAM modules at least twice and always on 2 different boards. Iirc the other board I used for testing was either an LX or a BX board.

It's not always plug&play with RAM (though it comes pretty darn close). Sometimes it takes a little work, especially with those early VIA boards or at least that was my experience with them.

IMO you can't get reliable results with just 1 board, some modules will not work in some generations boards. So best would be BX+815+845.
- BX will cover P 1-2 era 32-128MB, if it works here it would work on TX and with 99% on good MVP3 or Alladin;
- 815 is a tricky beast with crippled compatibility, it could eat later P4/Athlon era modules, refuse to work with early 32-128 MB modules and vice versa, thanks god compatibility doesn't take into account brand of mobo, it works or not;
- 845(or SiS 645/VIA 694/KT133A) will cover later 128-512 modules , may not work with early 32-64 MB modules.

I test my modules on QDI 10T board with VIA 694T chipset. It work fine with all my SDRAM sticks 32-512. Maybe today I will check 16MB EDO DIMM

appiah4 wrote on 2020-10-06, 21:38:

Well, the board in question that I am using now is a VIA PLE133T Socket 370 and it is VERY picky about RAM, it does not seem to be just about how many Mb the chips are, but even their configuration - ie the wordsxwidth where the width appears to be critical as well.

Maybe an early Athlon board is a better idea?

I'd say that's a specific board issue, not chipset - all Via chipsets from that generation, including 694X (ApolloPro133A), KT133(A) etc have the exact same memory controller. I also have a PLE133 SBC system and it's a complete slut, eats any DIMM I throw at it. I don't use it for testing though, but that's because I have a nice DFI TA64-B board with 694X, universal AGP, PCI, ISA, So370 FC-PGA and Slot 1 all together. Now *that* is a great test board 😜