Thank you for being a valued part of the CNET community. As of December 1, 2020, the forums are in read-only format. In early 2021, CNET Forums will no longer be available. We are grateful for the participation and advice you have provided to one another over the years.

Thanks,

CNET Support

Resolved Question

How much leeway with power supply wattage?

Jul 16, 2017 9:38PM PDT

I have Gigabyte GTX 670, and it's recommended power supply is 550 watts. I did a wattage calculation from http://www.coolermaster.com/power-supply-calculator/, and my load wattage is 491 watts. I have a 500 watt Cooler Master power supply, the cooler master rs-500-pcar-a3. I don't know if the load is too close to the power supply's limit. How much leeway do I have on the load wattage; For example 10 watts above the limit?
Should I overclock my CPU less so I have less load wattage, or should I not worry about it?

Discussion is locked

Jimmy Veasey has chosen the best answer to their question. View answer

Best Answer

- Collapse -
It's likely over at this point. Why?
Jul 17, 2017 5:24AM PDT

Because the rating is for a new supply and as the supply ages it loses capacity you want from 150% to 200% headroom on PSU capacity.

Also, it gets more complex as you reach the edge of capacity. There are about four voltage rails in most PSUs so for each rail there is a maximum plus a total for all combined.

While your 500W model might work, it usually fails later or has odd freezes, lockups and BSODs that make the PC experience an awful one.

- Collapse -
Answer
Psu
Jul 17, 2017 8:39AM PDT

That psu seems to be dual rail type.

Best not to use that type for a gaming rig.

Shop for a 600w+ quality single rail psu.

Best not to spec these things too tight having some extra won't hurt anything.

- Collapse -
Is this a good PSU?
Jul 17, 2017 12:29PM PDT

I found an EVGA 100-W1-0500-RX for 35 dollars on newegg. Is this a single rail psu? I don't know much about pu specs.

- Collapse -
While you are skimping on total Watts.
Jul 17, 2017 12:44PM PDT

This shows a single rail.

(newegg.com)

I can't guess why you are skimping on total Watts here. It's like a car. Drive it at 100 MPH and it will break down in no time.

- Collapse -
Nod to the 650.
Jul 17, 2017 3:33PM PDT
- Collapse -
Good...yes
Jul 17, 2017 3:25PM PDT