Upgrading CPU (Component Check) / Erasing HDD

Well I posted this in the CPU section, but I think this fits in this section better so posting here.



Hello. First I want to say thanks to anyone who is able to help me!

I currently have a HP M8430F desktop. (I know, I know, I will never buy another factory built computer again   )

http://h10025.www1.hp.com/ewfrf/wc/document?docname=c01...

Not having the money to purchase a new 2500k setup with all the goodies I want I am going to go the budget route and going to upgrade what I got. The computer is stock except for a Antec Earthwatts 750W Power supply and a NVIDIA GTX 460 GPU. Currently in the newegg cart is:

http://www.newegg.com/Product/Product.aspx?Item=N82E168...

http://www.newegg.com/Product/Product.aspx?Item=N82E168...

http://www.newegg.com/Product/Product.aspx?Item=N82E168...

http://www.newegg.com/Product/Product.aspx?Item=N82E168...

I can run the games I play now (SWTOR and BF3) pretty decently, but multi-tasking (running a internet in the background behind a game, etc.) I can def. feel the computer struggling. I'm hoping that with the upgrades I'm getting I can take the CPU from 2.4GhZ to the 3.0 and beyond range. Did a little reading about it so far and it seems doable/reasonable.

(One example here http://www.bit-tech.net/hardware/cpus/2007/07/25/overcl... )

Did a lot of reading before picking the Mobo I did, and it seems the P45 outshines the G41 for OC'ing purposes which is why I picked the one I did. Hoping with the CPU OC'd, double the memory, and having the GTX 460 the computer will perform better.

The purpose of this post is to get a quick cross check with you enthusiasts to make sure the pieces I picked are good and compatible, as well as to get any input, suggestions, feedback, etc. I'm not computer illiterate, but I'm also not a hardcore builder so I welcome any advice you guys have!

The last question I had was since this is a HP factory computer the hard drive is partitioned, as well as has all of the info on it from me using it for 4 years. I was hoping to re-use this HDD since it is a 7200RPM 750GB which is plenty of storage space for me. That being said I was wondering how to remove the partition from the HDD and then completely wipe it, operating system and all since I am upgrading to 7 from Vista. Essentially I want the HDD to be cleared so it was as if I was pulling it brand new out of the box.

Once again thanks for any help you guys can provide me with this!