DDR 333 and DDR 400 Memories.

My cousing brought to me a computer to verify it and she told me that it's constantly crashing and I though it could be memory. I've been reinstalling Windows and the blue screen of death appeared with a 0X0000...thingy. That's why I think memory is the problem.

But now I want to test my memory into her computer, but the problem is that mine is DDR 333 and hers is DDR 400 (they operate at different clock speeds).

All I wanna know if I can safely put my DDR 333 memory into her computer?

try running memtest86 (http://memtest86.com/) before swapping the ram around.

you need to tell more specs of the computer before i can accurately say if it 333 will work in her's. manufacturers pretty much always use 400 in their computers even if they don't need the ram to be that fast because its cheaper to just use the same sticks throughout their lineup.

If hers is running at DDR400 speeds and your chips max at DDR333 you are running the risk of more crashes, or the PC not turning on period. If her computer is set to autodetect the RAM and adjust the speed asynchronously (out of sync) to the FSB then you may not have a problem

I did the memtest thing... no problem.
Her computer has autodetect RAM, switched to 333... no problem.
Tested her computer with my RAM... 3 crashes (2 of them with blue screens of death).

What could be the problem? Motherboard?

It's a Biostar.

Could be heat related crashes, it could be a power supply going bad also.
A totally defective motherboard would be down the list I think.

But I did have an interesting discussion with a friend who had a PC crashing and rebooting at random for years. Power connectors on his PSU and mobo were burnt out. lol

I'd say first keep the case open and run some stress tests on it to see if it crashes, etc. Keep some airflow on it also.
Other than that, you can try swapping out the power supply with yours.