Mysterious CPU/Memory Behavior When Overclocking

[oldbutdumb]

I have a DFI Lanparty B ultra 400 motherboard with the 11/27/03 bios. I got it to overclock by using 11-2-2-2 timings and a multiplier of 16.5. The FSB setting has no effect on the cpu, only on memory. I was running nicely at a fsb of 285 based on Si-Soft Sandra V5. I got the equivalent of a xp 3200+ out of my xp 2500+ cpu. Then I used memtest to see if the memory was running without error at that setting. I ran it for a day and a half with no errors. So I tried to use a fsb of 300 and I got no errors. Then I tried to use timings of 6-2-2-2 and I got no errors. When I again tested with Soft Sandra the computer had slowed significantly in memory speed. I tried backing up but all to no avail. It is as though something conked out during my testing and fiddling with the bios. Now I'm running like a xp 2000+ and if I try to go any faster I get a lockup. My other settings should be in my profile. Anybody have a guess as to what is going on?

 

[oldbutdumb]

It occurs to me that I may have lost one stick of memory and the system is running on the other. I don't know what memtest would do in the case of one dead stick present. All I know is that it said 0 memory errors. It was necessary to have the dimm voltage set to 3.2 volts to get the thing to overclock. That may have fried the dimm during the test or something.

 

[SagaLore]

Originally posted by: oldbutdumb
It was necessary to have the dimm voltage set to 3.2 volts to get the thing to overclock. That may have fried the dimm during the test or something.

That may very well be the problem. Only put in 1 stick at a time and run your tests to confirm it.

 

[oldbutdumb]

After a long test I find that the memory sticks are ok. The wierd behavior seems to be a problem in the mb design. many bios upgrades have been written each to fix certain problems, but each causing new problems. I certainly would determine if DFI has properly designed any new system such as the one reviewed here:http://www.anandtech.com/mb/showdoc.aspx?i=2337 before I purchased one, even if the specs sound spectacular.