Need help with new power supply purchase

stormy13 said:

No the card doesn't require 500W itself. That 500W that video card manufacturer's recommend is for the system total, and is always higher than actually needed to take into account people using low quality no name power supplies.

This,

ASUS GeForce GTX 550 Ti Direct CU 1 GB Review | techPowerUp

will give you an idea of what the card actually uses.

Right.

The Asus card comes very close to the 150W nominal limit for a PCI-E card with a single 6 pin auxiliary connector.

Actually, the eVGA requirement is surprisingly low. Not so much the total power as the +12V current. However, a PSU like a Corsair CX430, while only a nominal 430W PSU, is rated at 32A at +12V. That would be more than adequate for your current system. I'd recommend going to a larger capacity, though, mainly because the price increase would probably be small.

The Corsair HX750 is about twice the PSU you'd need with your current PC. Overkill, unless you're buying it to move to a monster system later. Why not an AX1200? That's be triple what you'd need. It wouldn't be quite enough to handle four Radeon HD 7970s in Crossfire, but one must make small economies.

(Sorry. Got a bit carried away. Sometimes I think I've stumbled into a PSU fetishist site.)

Layback Bear said:

Corsair Gold or better would be very good now and for use in the future.
Modular would even be nicer.
Check the price difference between a 700 or 750W and a 850W. Sometimes with sales their is very little difference. Their is no such thing as to much power.

I believe I heard something about a PSU being bottlenecked and not achieving it's full efficency if you give it a system which doesn't get close it's peak wattage.

Erick Aguilar said:

Layback Bear said:

Corsair Gold or better would be very good now and for use in the future.
Modular would even be nicer.
Check the price difference between a 700 or 750W and a 850W. Sometimes with sales their is very little difference. Their is no such thing as to much power.

I believe I heard something about a PSU being bottlenecked and not achieving it's full efficency if you give it a system which doesn't get close it's peak wattage.

80 Plus - Wikipedia, the free encyclopedia

An 80+ Gold certified PSU is above 87% efficiency at 20% and 100% of its rated power, with a higher efficiency within that range. If true, there's no issue.