Would this be a worthwhile upgrade?

[Mr Men]

Hi all I am looking to upgrade my current mobo and CPU which is a Dell with a P4 3.06ghz, I dont have mountains of money to spend and would rather not if I am not going to see much gaming benefit, anyway what I was looking at was

AMD Athlon 64 4000+ San Diego 90nm (Socket 939) - Retail (ADA4000BNBOX) (CP-120-AM)

Asrock 939Dual-SATA2 (Socket 939 & Upgradable to AM2) AGP & PCI-Express Motherboard (MB-002-AK)

I would like to keep using AGP for the time being due to the card I have which I dont want to replace (a 7800 GS OC) at this time.

Would this be money well spent or should I just save more and wait my time?

 

[Mr Men]

Oh yeah I will be getting a new case and psu to go with it as the dell thing is disgusting and only a 250w PSU

"Get the 3700 SD instead, it'll clock easily past 4000 speeds on that asrock board."

hee hee I did have that on my list to start with, then changed my mind, but would I be getting a decent gain over what I have now? as a few people have told me the P4 is crap basically

If I get the 3700 sd to overclock it should I bother with the retail version or better to buy another cooler instead?