Hi there
I'm currently running a 6850 and a 5850 on a 600W Corsair PSU in:
Corsair 600W CX Builder Series 80 Plus PSU
Core i7 2600k
Corsair Vengeance 8GB (2x4GB) DDR3 1600Mhz
Gigabyte GA-Z68X-UD3-B3 Z68 Socket 1155
Arctic Cooling Freezer 7 Pro rev 2 Socket 1155
1 SSD
1 HD (7200)
3 120 MM fans
1 140 MM Fan
1 DVD RW
Will i be ok to replace my 5850 with a 7950 and keep using the same PSU or am i going to have issues?
Also what happens if you draw too much power from your PSU does it shut down or blow?
600 watt isn't going to cut it...
You would push close to 600 watt for the whole system with just the 7950 overclocked (almost 400 watt [369 watt battlefield load tested] use for the card itself) pushing full load, a non overclocked version will push 250 watt [235 watt battlefield load tested] system draw as well. Add in the 6850 at around 250 watt (229 watt 3dmark06 tested) and you're asking for disaster.
Power is very important and it can behave is unexpected ways meaning a simple shut down because too much load to the extremes of blowing multiple parts in your system and at the far end of the spectrum and rare but possible causing a fire.