I have an nvidia 610i chipset with on board geforce 7050 graphics with 256mb memory. (shared from my 2 gigs of ddr2 800) when i first built this machine, it played videos like crap. for some reason i tweaked the mhz on the north chip (i think) and now it plays videos fine. now i am working in auto desk viz2008 with a city, and it seems like the computer is starting to hiccup. the stock mhz was 500, i set it to 600, and max is 2000. how far do you think i can take this thing before i damage anything? i have pretty good airflow through the case but no specific fan is mounted to the north or south chips. I'm curious if 700 or 750mhz will make this thing cruise a little faster... thanks!