I have a factory built HP system that is slowly going out of date and I'm thinking of taking the Pentium D 820 Smithfield out of it and building a micro atx tower to overclock.
I've read quite a few reviews and threads that the smithfield architecture leads to monstrous ocing ability and thats just what I want to do with it. I will basically use everything in the PC except for the motherboard, case, RAM and heatsink(obviously).
i did a D820 a long time ago... I got it to 4.2GHz Cant remember any settings though, was using a bad mobo as well... i used one of my custom water loop systems filled with anti freeze and i had dry ice on top if the radiator... that was cooling the whole system NB SB, Ram AND CPU... Cant even remember why i didn't push it further
Wait so you already have an I5 but your wanting to OC the Pentium D just for the heck of it? Are there any target games you wish to play with this rig?
Pentium D's have a terribly low IPC, so low that a Core 2 a full GHz+ below it in clock speed can still beat it, at this point you may get more perfromance by buying a lower end Core 2 or "Pentium Dual Core" that would probably outperform a 5GHz+ Pentium D when overclocked.
Some games like Valves source engine games don't support dual core support on Pentium D cpus which leads to poor performance in newer source games.
If it's just wanting to overclock the Pentium D because you have an attatchment to the chip or just want to see that spesific chip overclocked I hear ya there, I have a 3GHz Pentium D 925 that I would never sell simply due to the fact that it was from my first decent sped'd pc. (I came from an 850mhz amd duron)
It's faily easy to make sure you don't fry your cpu while overclocking.
Just by raising the fsb it's very hard to fry your chip, just make sure your temps are fine. Usually it's only when you start overvolting your chip to get insane overclocks do you run a risk of frying the chip.