Syntho wrote on 2024-08-13, 10:01:
[...]
I think I've located the chip you mentioned. It doesn't look bad to the naked eye, but I don't think getting in there and unsoldering it would be worth it. While I don't know how how all of that stuff works under the hood, I'd think that the system wouldn't work at all or at least give me trouble if something weren't soldered right with the old RAM in there. But it's worked fine for 3 years now.
Not necessarily.
A chip like that has multiple (13 in this case) address lines. If a certain address line is pretty high up it will only be used when there's a lot of RAM in the system. It's probably possible to say exactly which, although I'm not up to speed enough with addressing of tag ram to say which. My best guess would be that if 16MB does work but errors start above that, given the chipset can cache max 64MB, the problem would be 1/4 of the way into those 12 lines, so pin A04 would be my first suspect. Alternately it's a binary encoding instead of a mapping and then I'd suspect A01 or A11. I'd focus strongly on those three pins and the traces leading to them.
DOS works fine. It's Windows that doesn't work, both 95 and a 98SE installation. So maybe some sort of weird Windows setting is conflicting with the new RAM, and a reinstallation will fix it. Ridiculous, but maybe worth a try to install a new copy of 95/98SE...
DOS only uses a few kB of memory and even late DOS games tend not to use more than 4MB or so, so you don't hit the addresses where it's going wrong. Probably you'd see issues too if you ran anything that actually used more than 16MB.
Syntho wrote on 2024-08-13, 15:01:Alright, I tried reinstalling Windows. Doesn't work. Something is very weird about this whole thing and I don't know if it's wor […]
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Alright, I tried reinstalling Windows. Doesn't work. Something is very weird about this whole thing and I don't know if it's worth it to keep debugging it. 16mb of RAM works. 32mb or more doesn't.
When I have 32mb in there, Windows restarts immediately. With 64mb, it freezes.
For reinstallaing, 64mb freezes the installation, but 32mb gives me:
A Fatal Exception 06 Has Occurred at 0B33:00000092. The current application will be terminated
The only other thing I can think of is that my original 8mb sticks are period correct. The other RAM is newer stuff from Ebay. Maybe some sort of spec changed and the way they manufactured the RAM changed over time and my motherboard just plain doesn't like newer stuff. I'd have to track down some older RAM, but I really don't want to keep buying stuff over and over. I'm out of ideas other than that.
Occam's Razor: the simplest solution is usually the correct one.
Yes, it's possible there's something weird going on with compatibility on newer processes and higher densities (despite everything you're using explicitly being supported according to both manual and chipset datasheet). Or it's just a cache failure once you get beyond a certain amount of RAM.
A test that would prove this one way or another: get another two 8MB SIMMs. If I am correct, both will work perfectly when used separately, but you will have exactly the same issues as with the 2x 16MB SIMMs if you install all four 8MB SIMMs at once.
DudeFace wrote on 2024-08-14, 00:02:
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dont use EDO ram, i had nothing but problems with mine also two 8mb sticks, sometimes i wouldnt get any video out and when i did installing windows was impossible it wasnt reliable, and prob because the onboard video was using 4mb of it, also dont use two different types of ram at once, according to the manual for my board (socket 7) it can cause damage, which didnt occur to me.
With an i430VX chipset? EDO was well established then, was the default to use and should always work assuming the timings set on the board are within the specs of your SIMMs (so at most 60ns SIMMs if using 66MHz FSB).
As for the 'can cause damage', somebody is getting confused. Maybe you, maybe whoever wrote the manual. EDO and FP are electrically identical so no damage will arise if mixing them, not to the SIMMs or the board. It just won't work.
What can damage parts on a board like this is combinging 3.3V DIMMs (EDO or SDRAM) with 5V SIMMs. In that case the memory will all get run at 5V which will fry the DIMMs unless they are 5V tolerant
you mentioned changing/resetting the bios then having problems, three options to look out for are "memory hole at 15-16M", "shadow video bios" or cache bios/video bios" disable all of them, the memory hole one if i remember will prevent windows from booting so expect to do a fresh install.
It can't hurt to check, but these are all memory-related options while the problem is in cacheing, as proved by the fact all problems go away if cache is disabled.
