looking to upgrade processor

Due to limitatations provided with my 2.40 ghz intel celeron processor when playing games, I am looking to get something meatier. Can anyone recommend any good quality ones (that wont cost the earth, put provide a better performance). The processor must be compatible with a mPGA478 socket

my current rig

2.4ghz intel celeron
IM845G motherboard
1 gb ddr memmory
nvidia 6600GT graphics card
AC 97 integrated sound card (soon to be replaced)
500 watt PSU

It depends on what FSB your motherboard is capable of taking, I can’t find anything on that motherboard at the minute but the P4 range is what you’re looking at, if you had the money a CPU & Motherboard upgrade would be good and you could look into the AMD64 line…

Yeah it depends on what FSB your mobo can take, but I think you can get P4 3.0 ghz with 533 fsb, not sure though.

Either this: http://www.newegg.com/Product/Product.asp?Item=N82E16819116171
Or this: http://www.newegg.com/Product/Product.asp?Item=N82E16819116180
Depending on what FSB your mobo can support. The 478 boards often go up to 800MHz though.