I'm running an emachines 570 which I have upgraded the memory to 568mb as I'm a gamer I need something a bit zippy!, I want to upgrade the Intel Celeron 2:00Ghz, (speed 199Ghz) but I'm not sure what I should upgrade it to! My weedy Power Supply is a mere 250W I'm afraid! Incidently, it must sit in a mPGA478 Socket! any ideas? tyvm.

You need to find out what your motherboard and BIOS will support. That is the limitation.

I cannot find that model at eMachine

http://www.emachines.com/support/pro...s&subcat=Other

If your motherboard will support it, the biggest processor that you can upgrade to on socket 478 is a Pentium 4 2.4GHz. After that, they all went to socket 775. Might be worth having a look at www.evergreen.com - they manufacture upgrade processors specifically for people who want more speed than what their motherboard will theoretically support

Sorry, wrong link - should have been www.evertech.com but, unfortunately, it looks like the company has gone under as their domain name has been taken over by a big weight loss advert!