Computer Upgrades - Looking for bang for the buck

[Concillian]

I'm not sure about adapters, but chances are if your PSU doesn't support the correct lines it's likely it doesn't put out adequate power for the card. If the video card isn't getting enough power you can find yourself getting all sorts of issues with your system and it pretty much negates having an upgraded card as it will probably perform just as bad as your old card or worse. These issues can eventually end up burning out the card and possibly other components.

This usually isn't an issue with a moderate CPU. I use a 330W supply with overclocked 4850 and dual core CPU and it's fine. My power meter says I draw barely over 200W when I try to load it as fully as I can. As long as you're not running like a 4+ core CPU or crossfire / SLi most PSUs can handle a regular machine and a 5770 (which barely draws enough to require one of those connectors.

You still want to lay out your expected power draw to make sure you're covered, but PSU requirements are generally pretty exaggerated unless you're getting some kind of system that's WAY beyond the average gamer machine (I'd consider an average gamer machine something like a i3 / x3 + 5770 in current models)