krells :
Can you post the exact model PSU since they make a few different 600w models? You need 31A on the 12v rail and 550w minimum to run the 290.
Product no: RS-600-ACAB-D3
switching power supply ATX 12V V2.31 w/active PFC
AC INPUT: 200-240V~ 5A 47-63 HZ
DC OUTPUT: +12V +5V +3.3V -12V +5Vsb
47A 20A 20A 0.3A 2.5A
MAX POWER: 564W 120W 3.6W 12.5W
600W
Sorry, I'm pretty new to this...
I think its 47A on the 12V rail if I'm not mistaken...