Memtest not stressing RAM enough?

[996GT2]

Got my CPU to 2.8 GHz stable at 1.375V lately, so I decided while I was at it to try to bump up DDR2 speed too. Previously I could not get my DDR2 stable past 750mhz at 4-4-4-12 timings so this time I tried the DDR2-667 divider on my mobo for 800mhz effective speed with worse timimgs. Turned down timings to 5-5-5-12 from stock 4-4-4-12, increased VDimm to 2.1V. At this setting it appeard stable in memtest+ with 20+ passes of test 5 and 10+ of test 1 before I stopped testing. However as soon as I get past the windows login the entire comp freezes. I don?t think it?s my CPU because the setup at 2.8 GHz is prime/superpi stable at DDR2-620 (using the 533 divider). Can someone explain and suggest a more rigorous test in memtest if there is one?

 

[cmdrdredd]

Originally posted by: 996GT2
Got my CPU to 2.8 GHz stable at 1.375V lately, so I decided while I was at it to try to bump up DDR2 speed too. Previously I could not get my DDR2 stable past 750mhz at 4-4-4-12 timings so this time I tried the DDR2-667 divider on my mobo for 800mhz effective speed with worse timimgs. Turned down timings to 5-5-5-12 from stock 4-4-4-12, increased VDimm to 2.1V. At this setting it appeard stable in memtest+ with 20+ passes of test 5 and 10+ of test 1 before I stopped testing. However as soon as I get past the windows login the entire comp freezes. I don?t think it?s my CPU because the setup at 2.8 GHz is prime/superpi stable at DDR2-620 (using the 533 divider). Can someone explain and suggest a more rigorous test in memtest if there is one?

Run the entire series for 24hours

 

[myocardia]

24 hours is a bit long. Most of us don't do more than 8-12 hours of MemTest. Plus, you do realize that nearly all 965-based motherboards don't like overclocking with the memory at anything besides 1:1, don't you?

edit: You should have been trying 5-5-5-15, anyway, not 5-5-5-12.