Windows 7 - PSU/Graphics fit?

Hello
I am about to upgrade my system, using the same Giga EG41MFT-US2H Mobo, but changing a Core2 Duo to a Q6600, the ATI graphics from a 5450 to an Asus HD6770, upgrading the RAM (4GB, 2x2), second Hdd 1 TB. Seagate. The PSU is an OCZ Stealth X Stream 500Watt.

Question I have: is the PSU going to have the necessary power? It has the 12v 6-Pin power connector, but will it have enough for the whole system? I really do not want to replace it, it is a cracking PSU, never given any problems and runs well under spec's with my current setup; but if it is not powerful enough, I will have to.

Thanks, all.

Hi Bertison.

Here are two power supply calculators that I like:

ASUSTeK Computer Inc. -Support- Recommended Power Supply Wattage Calculator

Newegg.com - Recommended Power Supply Calculator.

It should be fine. I have a similar spec'ed power supply (Antec Earthwatts 500W) in my kids computer powering a HD 4830/Athlon II x4 630/4 GB ram/etc, without any issues at all.

Thanks, Lemur.
As the current PSU shows on the site spec's that it has an over volts cut-out, I will try it. If I suspect that it won't do the trick, out it comes and in goes a 650Watt.

btw, the Newegg page "Cannot Be Found" from here.

The Newegg and Asus calculators both overstate how big a PSU is needed. A good quality 500W is more than enough for what you plan. This one is a little more accurate as to what is needed,

eXtreme Outer Vision - eXtreme tools for computer enthusiasts

There are lots of calcs out there. Some probably do overstate, while others may understate. It might be worthwhile to examine a few from reputable sites and take an average. Here is another from MSI.

MSI Global ? Power Supply Calculator

GPU should not go above 200W, CPU should be no more than 100, add another 100 for motherboard, hard drives, DVD etc., for 400W total max. Unless your power supply doesn't meet the specs, you should have no problem. Sometimes you could be in trouble if one voltage output draws much more than expected, in other words you could be bellow 500W max total but go over the maximum on 5V or 12V lines, but I think you should be fine with 500W. You probably could undervolt CPU, those older Intels usually run fine on much lower voltage than nominal and that will make them run cooler and probably more stable, even if overclocked.

The graphics card can't draw more than 150W. The Q6600 is rated at 105W. I believ that most of the power for both is derived from the +12V line. (That a bit over 21A total.) Your OCZ PSU appears to have two +12V rails, at 18A each. It's specified for 432W max total at +12V so all 36A are supposed to be available.

If you wish to do a major overclock of the Q6600, its power dissipation could get up around 200W. The 500W supply would probably still be adequate, but you might want more margin.

I think that some of the PSU calculators return high wattage numbers to cover inexpensive power suppplies. A good 400W PSU:

Newegg.com - PC Power and Cooling Silencer MK III PPCMK3S400 400W ATX 12V v2.3 80 PLUS BRONZE Certified Modular Active PFC Power Supply

can offer as much or more +12V current as a cheap 600W unit:

Newegg.com - Broadway Com Corp OKIA-BLACK-600 600W ATX 12V V2.2 SLI Ready CrossFire Ready Active PFC Power Supply

Buyer beware.