P5Q3 E8400 overheating issues

Hi,

If anyone can advise it would be greatly appreciated

My system parts that i think are relevant are

Asus PQ53 E8400 3.00 duo core 2
Gigabyte HD 4870 1GB graphics card
M5 Thermaltake case - 1 fan on top sucking out above heatsink, 1 fan at back in line with heat sink sucking out and 1 fan at front blowing in across hard drives
Power Supply is a OCZ600MXSP

I am suffering from overheating, above 70c and blue screening. The heat seems to be coming off the graphics card in waves rather than out of the heatsink. I've had PC's for years but i am more software guy than hardware.

I'm wondering if i just need some much better fans or a better heat sink. I am currently using it with the side off and this is not good. the fans are at between 1800 and 2200 rpm.

The processors came with arctic silver and attached

Thanks

David

what cooler are you running on your cpu? If you put a box fan up to the side of your case, do you see sizable temp drops?