Hi guys, I'm wondering if I can overclock my gpu(gtx 580)/cpu(i7 2600k) much with a 700w power supply from OCZ? A 600w psu is recommended when running a 580..does this leave me with any headroom to overclock?
You can determine exactly what your current or future PC configuration will require for wattage and amps. on the 12v rail(s) by working thru the information below. You start by checking the Video Graphics card wattage then convert that to 12v rails amps. and check out PSU reviews to see if your current or potential new PSU can deliver the amps. you need on the 12v rails. It's pretty easy and once you know how to do it you'll be in a position to not only help yourself but also help other folks learn.
There are several websites that show the Graphics card power consumption in watts. (See the links below). Divide the watts by 12 to determine the amps. required on the 12v rail(s). Add 15 amps for the rest of the PC on the 12v rail and you now know the Minimum total 12v rail amps required under full load. It's best to have at least 5-10 amps. reserve on the 12v rail available under full load so the PSU is not loaded to 100%.
Here's an example:
Say your Vid card draws 240W under max load. Divide 240 by 12 to get 20 amps. on the 12v rail. Add 15 amps. for the rest of the drives, fans, etc. and you have 35 amps. Add 5 more amps for a minimum safety margin when the PSU gets hot under full load and your end up needing <40+> amps. total on the 12v rails.
If your PSU has a single 12v rail and it delivers 40+ amps. under full load then you are in good shape. If not you need a better/larger PSU. If you have a multi-rail 12v PSU then you need to check the label to see what the combined amps output is for the 12v rails under max load. If it's 40+ amps. combined, then you're good to go. If not then you need a better/larger PSU. The individual 12v rail max amps. may NOT be the same as the combined 12v rails max amps, so check the label and read proper PSU reviews to confirm the PSU is quality built and can deliver the claimed amps. under max load and temps. This is important for stable PC operation.
240W/12 = 20 amps + 15 amps. for the rest of PC + 5 amps. safety margin = 40+ amps. required
As far as PSUs are concerned, be informed. Before you buy any PSU, read accurate, objective PSU reviews at reputable sites such at Toms', www.jonnyguru.com or www.hardwaresecrets.com on the EXACT model PSU that you are interested in as some brands have good and poor quality PSUs.
It's also worth noting that people often misunderstand the 80% power rating. This is a rating of the PSU's energy efficiency not it's output. 80% plus PSUs use less grid power to produce the same PC power. If it's 80% Bronze, Silver or Gold the cost savings on electricity is pretty small between Bronze, Silver and Gold unless you are paying very high rates for electricity so any 80% rated quality PSU is fine even if not Gold. For those who leave their PC on 24/7 a quality 80% PSU is a good investment.
For a basic PSU calculation you can determine the total power (wattage), required for your current or future system at the PSU calculator link below. Once you know the total PSU watts required then you need to confirm that the 12v rail(s) has enough amps. to support your Grapgics card(s) and the rest of the PC system as shown above in the calculation example.