Any input on this one. Installed a new video card on my system , an HD5850, and when I started my system my MOBO would not post, no beep(s) nothing. No power to keyboard, mouse, and obviously the monitor was black.

Called ASUS support and they told me my power supply wasn't good enough. Now the minimum power rating for the vid card it 500 and I had an Antec 550 supply. I wanted a new one anyway as I plan on building a new system so I went out and bought a Rosewill 850 supply. Got the new supply and still nothing. Put the old 1950PRO card in and all is cool. RMA'd new card to newegg. My MOBO is an epox 9npa+ nforce4. I know its older and I really don't think that the MOBO is the problem. Just looking for additonal input on this.