Safe PSU wattage to overclock

Hardware Hub Overclocking
1

Would i be able to overclock either my GPU or CPU with only a 500W Moduclar antec PSU or would it be better to buy a new PSU first?

I am currently running:
ASrock 970 Extreme3
AMD FX-4100
EVGA 650ti 1GB
Antec 500W Modular
OCZ 60GB Vertex 2
Samsung 1TB (not sure what model but its at 7200rpm)
WiFi PCI card
 

 

2

Will be fine, with your specs you can safely oc both with plenty of extra headroom still remaining.

3

You'll be fine. As long as you don't add too much on the system afterwards. But as usual, it's always better to have a surplus of wattage to work with, do I'd recommend getting a new on anyways.