My system is as follows..
Motherboard: MSI Neo2-FIR with the latest BIOS
CPU: Q9550 OC@3400 MHz
RAM: 8 GB OCZ DDR2 REAPER HPC PC2-9200 1150 MHz (2 X 4 GB) http://www.ocztechnology.com/ocz-ddr2-p ... ition.html
OS: Windows 7 x64 SP1
Gfx: Nvidia 9800GT
I bought the RAM around two years ago because it was on sale and was just about the fastest DDR2 RAM I could buy. Pretty soon I found out that my motherboard didn't support it and I had to fiddle with settings in BIOS by looking at the meager info available from the manual and searching the OCZ forum. After doing some guesswork I managed to get the system stable and it has been running stable for almost two years.
Last week, however, it started to randomly bluescreen. Most of the errors are PAGE_FAULT_IN_NON_PAGED_AREA but I've also seen MEMORY_MANAGEMENT at times. It doesn't seem to matter whether the computer is idling or is under heavy load, its completely random.
I tried not overclocking, underclocking, raising/lowering the FSB/CPU/DRAM/SB/NB voltage, running diskcheck on all harddrives (no errors), running the windows memtest (no errors), running memtest86+ (5+ passes, no errors), running prime95 (all three tests, no errors) and making sure all PCI/PCI-ex cards, cables and everything inside the case weren't glitching.
Finally I think I found the culprit: somehow the BIOS had reset its settings and the DRAM was running at default settings, which is something bad if the memory is unsupported by the motherboard. It was overvoltaged and all the settings were way off according to what it should be looking at OCZ's homepage. Unfortunately, I haven't been able to guess what the settings should be since I lost the postit note where I'd written it down a long time ago.
These are the current BIOS settings I'm for the DRAM:
FSB: 400 MHz
FSB/Memory Ratio: 1:1.25 (1000 MHz)
DRAM CAS# Latency: 5
DRAM RAS# to CAS# Delay: 5 DRAM Clocks
DRAM RAS# Precharge: 5 DRAM Clocks
DRAM RAS# Activate to Precharge: 18 DRAM Clocks
DRAM TRFC: 50 DRAM Clocks (this is the one I'm very unsure of what it should be)
DRAM TWR: 6 DRAM Clocks
DRAM TWTR: 11 DRAM Clocks
DRAM TRRD: 11 DRAM Clocks
DRAM TRTD: 11 DRAM Clocks
If a technical genius that actually knows what all these DRAM 4-letter stuff stands for could help out, I'd be most grateful. Or for any advice about where the error could be, perhaps it's not the DRAM settings after all.