Testing memory

[MerePeer]

I added a stick of ddr sdram to a machine a few weeks ago and since then it occassionally just 'stops' during the boot process during the loading of windows. Resetting the power clears it up, except one time it took third try. It runs for days after that. I'm wondering if anyone can suggest software that tests the memory for problems?
TIA

[the-mk]

http://www.memtest.org/

I haven't used that from their site, but I used it from some old SuSE Linux CDs and it worked fine... I've sorted out some RAM modules, because memtest said, that they were bad...

[Supp]

it's on gentoo live cd, suse live eval...