I've tried 1.8, 1.85, and 1.95 for the ram, using only one stick in multiple slots, and still got the failures (no 1.90 option for some reason). I have other sticks of ram that work fine, in fact been running stable in the system 24/7 for years. I'm not sure on what tools to run on Linux though to verify it, I know way more of those tools on windows. And even then, I'm not sure if the machine will actually report actual voltage on the RAM, since it doesn't in the BIOS. Output of sensors in Linux is complete nonsense for the voltages. 6-6-6-18 is as loose as possible on the timings, didn't help.
Then given what you've said here and in your first post it sounds like a RAM incompatibility issue. Neither module of the new kit works regardless of voltage or timings, but the Crucial kit worked fine. Ya should probably stick with using the Crucial RAM, I've always read that they had the best compatibility record with their memory and this just seems to be another example at this point.
You must have misread or I was confusing. Both kits of ram are Crucial.
But, it works fine in 2 other Core2 Duo machines now. So I'm guessing I'm stuck with an imcompatibility. I'll maybe try some other things, maybe this will be my impetus to replace the home server with a newer one, because I want more than 4Gb in the server for VMs and stuff. I don't want to really drop more $$$ on DDR2 when DDR3 is soooo much cheaper. Kinda sad, though, the Phenom II box is my last AMD hardware, and I kinda wanted to keep it as it was the peak of the good AMD CPUs. Without using it for a server I don't have much use for it.
edit: I guess I didn't mention it, it is Crucial 2x2GB kit CT2KIT25664AA800. Lifetime memory warranties are somewhat of a joke at the lower end. I have to pay to ship it to the USA, and their warranty policy says you need to use original packaging. Maybe they'll warranty it, maybe the won't, and it will cost me 30 bucks to find out.