OC'ing My 6600GT

I have a MSI NX6600GT-TDI28E PCIe Graphics card. When I leave it at stock speeds of 500/1000(w/ stock HSF) I get a score of 3500ish on 3DMark05 and temperature under load during that time is about 66 degrees. When I over clock to 570/1200(w/ stock HSF) I get a score of 4146 on 3DMark05 and a max temperature of 77degrees. I know this is starting to get high. Do you think it would be beneficial for me to take off the HSF and apply Artic Silver 5 to the RAM and GPU and put back on the stock HSF. I plan to eventually get the Zalman V700 fan but not for a little bit. When I OC I do notice a big difference in the way BF2 plays on medium settings. Instead of getting40-70ish FPS, I get 60-80ish FPS.

Specs:
CPU: Pentium 4 3.0GHz
RAM: 1 gig(512x2) Corsair PC4200 DDR2 533
GPU: MSI Geforce 6600GT PCIe OC'ed 570/1200
HDD: Some POS Maxtor IDE(Official Playstation 2 HDD, My SATA drives are down)
MB: Biostar N4SIE-A7 Intel-SLi Edition
PSU: Powmax Demon 580Watt

 

got the same card if you'rew gonna get the cooler soon i'd hold off on the artic silver till then.

 

well I thought it was going to be soon. won't be fore a month atleast until I move and get situated with a new job.