Could you leave your PC off for the night and work the next day if you basically wake up and go to work, that could get close to 18 hours off potentially.
That's the normal daily procedure. And it's stable if it's only been off for about 18 hours. It's always stable, except on Mondays, when it's been unplugged for much longer than a day. One day won't cut it. That's the hard part about this thing. Even if I take out the sticks one at a time, it's going to take ages to find the culprit. And if I wait for too long before turning on the pc after I've plugged it in the socked, I may not even have any problems at all. So basically it's remove DIMM, leave unplugged for 40+ hours, boot, check memory. Once per DIMM, and then another few times. Meanwhile, I'd also like to use the thing - now there's two things that don't like eachother. But like I said, maybe I'll find the DIMM missing in the BIOS the first time I notice it's only 4GB again. But I'm thinking too easy aren't I?
Anyway, BIOS is back to default 8-8-8-20 memory settings, as apparently going 9-9-9-24 wasn't the solution after all.
Tomorrow I think I'll call the shop where I bought it. Maybe, just maybe they've seen it before. Never hurts to give it a shot, and to get them knowing that there is probably a hardware issue.
It's still at 1.5V though - any chance 1.6V might solve this recurring very temporary issue?
There's still this strange thing about the sound card (?) as well that's been bugging me for a while... in the PCI devices listing during the boot procedure, there's an 'ACPI controller' which has no assigned numbers. I do believe everything was filled when I first installed the pc. It turned empty when I first disabled the onboard sound controller, but never returned when it was enabled again. I don't know, something fishy may be going on in the BIOS, even after the CMOS reset. It shouldn't have failed after disabling hyperthreading either (though maybe that was the combination with memory timers?).