testing graphic card
 

I have a creative Geforce2 mx200, Athlon 1ghz, and 256M RAM.
I'm axperiencing troubles when I play counter-strike: I get random freeze
during the game that cause my computer to stop. I've already run a bunch of
tests on the mainboard (wich prove that the other 256Mb RAM I had was dead),
and I'd like to run some tests on the graphic card as well. I'd be
interessted in memory testing especialy.
Can anyone give me advice on how to do that? or give me some link to a good
graphic card tester.
any help will be appreciated