Computer build under $420?

[Migzzbleh]

Hello Tom's hardware, and MERRY CHRISTMAS TO ALL OF YOU! I need help on making a decent build under $420. My present pc specs are the ff:

PDC E2180 2.00ghz @ 2.5ghz
Asus p5gc-mx/1333
4gb DDR2
Gtx 650 oc edition(palit)
600w PSU
WD 320gb hdd.

I only need to upgrade my proce,ram,and mobo to be honest. I'm not really in that much of a need for a case. I'm open to using either an amd, or intel platform so long as it won't bottleneck the gtx, AND that it's mobo has at least one PCI slot(I have a wifi card that I want to use on the new build). I still plan to use the hdd, gpu, and psu and case. But I need the proce,ram,and mobo upgraded. Any suggestions please? I plan to use it for moderate gaming and some work (I'm a student) thanks again! And merry Christmas.

 

[Blaise170]

Throw in a new CPU, mobo, and RAM for under $350. Motherboard can SLI if you wanted to throw in another 650.

PCPartPicker part list / Price breakdown by merchant / Benchmarks

CPU: AMD FX-8350 4.0GHz 8-Core Processor ($198.98 @ OutletPC)
Motherboard: MSI 970A-G46 ATX AM3+ Motherboard ($69.99 @ Microcenter)
Memory: G.Skill Sniper Series 8GB (2 x 4GB) DDR3-1866 Memory ($68.00 @ Newegg)
Total: $336.97
(Prices include shipping, taxes, and discounts when available.)
(Generated by PCPartPicker 2013-12-23 23:05 EST-0500)

 

[Beezy]

a new motherboard and CPU is the best upgrade. Then next important upgrade would be a going from 4GB to 8GB of ram, and lastly a new or second GPU to run alongside the current