Hi...

I am running windows Vista Home Basic.

And I currently have a Pentium 4 531 (3.0 GHZ) and I am thinking of purchasing a Pentium 4 670 (3.8 GHZ)...

And I was wondering if reformatting the hard drive and reinstalling Vista is needed?

If so I might as well buy a bigger SATA hard drive.

I don't see why you would need to. Unless it's something new and 'improved' in Vista.

The processor has nothing to do with data storage. It should work just fine, but you might find you'll need to reinstall windows over the top. There should be no need to reformat though.

Thanks for the response... so are you saying I might have to reinstall windows? If I have to do that, then I might as well reformat... if I'm going to do that I might as well get a bigger hard drive.

Not reinstall, but maybe repair the installation. But PROBABLY NOT. Have a go first!

Installing a new cpu will not affect Vista or XP, you do not need to install or reformat. :)

Your main concern is whether your motherboard is compatible with the faster cpu. You'll need to refer to the motheboard users manual.

Thank you so much for the response!
Yea, I already checked the MSI's website on the CPU compatibility...

Just waiting for it in the mail!
Again thank you!