I know that Dells are not built for OverClocking and that you can't OC through BIOS, due to it being locked...

So, my question is, can I OC my dell using the Nvidia nTune software?
Or will the changes to the CPU just be blocked by the BIOS?

E6600 Core 2 Duo
BFG 9800 GT
4GB (4 x 1GB) OCZ Platinumrev. 2
Motherboard: Dell inc. 0CT017

If the software screws-up, will I be able to revert back to default by resetting the BIOS to default?

Hello j897655 and welcome.

Do yourself a favor and don't try overclocking a Dell.

If you want to overclock software is not the way to go about it and you should have premium equipment all around especially the cooling.

What you are contemplating is a recipe for trouble.

Thanks for the quick reply.
I was reading some other forums about nTune and it doesn't sound too bright... I think I will leave it and build a new system when DDR3 and Core i7's are a little cheaper ^^

Thanks for the advice!