The first thing to find oout is if your motherboard supports this CPU. If not, your choice is clear.
If you really have something to choose it depends on what you use the machine for. It could even be that adding RAM would be better investment of your money.
There's no general advice possible.
i want to spend my Christmas money on upgrading my emachine T6542 computer. i want to get an AMD Athlon 64 X2 6000 processor and a 512mb video card. right know i have an AMD Athlon 64 3500 processor and a 256mb Nvidia GeForce 7300 GS video card. I might not have enough to get both so i was wondering what i should get first. any help is apreciated. thx