Can i overclock intel pentium r d cpu 2 80ghz

Increase the FSB speed.
See the overclocking guide. It's the same as any of the newer Intel processors, just you're probably dealing with a 200Mhz FSB rather than 266 or 333 of the newer Core2 chips.

- realtemp to monitor core temperatures
- prime95 to stress test (for temps and stability testing)
- increase FSB until Prime95 fails
- increase Vcore
- prime95 to stress test + realtemp to watch temps
- repeat process until Vcore and temp are as high as you accept

That's the basics to begin with. You also need to watch your RAM frequency doesn't exceed its ability, and make sure you know where the Clear CMOS jumper is in-case it goes bad.

Also recommend aftermarket heatsink if you want better results.

Overclocking Guide: http://www.tomshardware.com/forum/240001-29-howto-overc...