How much wattage of PSU is recommended for this setup?

[NDDU Julius BSIT]

I have a friend whom I replaced his PC's PSU recently because his 620W PSU was undervolting (3 point something volts was at 2.455, 12 was at 10. something). We were able to replace it with a 550W PSU from a friend of his but just now he said he heard a pop and his PC won't turn on.

His Setup:
CPU: Intel Core i7-2700K (Stock speeds)
GPU: EVGA GTX 670
PSU: (Forgot the brand) 550W 80 PLUS Bronze
RAM:4x4GB GSkills DDR3 1600 MHz

with 6x120mm for the radiators and case fans

 

[mazboy]

This says you need minimum of a 500w PSU: https://forum-en.msi.com/faq/article/power-requirements-for-graphics-cards-20
And that would be a name-brand, quality PSU. One of these would work: http://www.tomshardware.com/reviews/best-psus,4229.html

 

[sizzling]

What 550w did you use, there is a huge difference between low and high quality ones.

 

[cryoburner]

A system with those components shouldn't likely draw more than around 350 watts from the PSU under load, so a quality 550 watt PSU would likely be fine. Many cheap, off-brand PSUs can't supply an extended load anywhere near their max stated capacity though, so knowing the brand and model might be useful to determine whether it may have been one of those.

 

[Lucky_SLS]

Have a look at this https://pcpartpicker.com/product/KmgzK8/seasonic-focus-gold-550w-80-gold-certified-semi-modular-atx-power-supply-ssr-550fm

 

[Aeacus]

GTX 670 is 170W GPU, add the rest of the system to it at about 200W and in total, you'd be looking at would be 370W.

Minimum would be 500W PSU but since the GPU is old, you'll also need at least 30A on +12V rail. Not all 500W range PSUs can deliver 30A on +12V rail. Here are few who can: Seasonic M12II-520 EVO (40A at +12V rail), Seasonic Focus+ 550 (45A at +12V rail), Seasonic G-550 (45A at +12V rail),
pcpp: https://pcpartpicker.com/products/compare/TgW9TW,DPCwrH,bkp323/

Do note that when you get a new PSU and PC still doesn't turn on then it's most likely that the old PSU took some components with it when it died.

 

[NDDU Julius BSIT]

I hope so not. He spent about $800 on that rig and it was still not fully paid

 

[Aeacus]

Most people learn the hard way not to cheap out on a PSU when low quality PSU blows and takes part of it or the whole system with it. Even entire houses have been burned down because of the fire low quality PSU caused when it blowed up.

You can cheap out on every other component inside the PC except PSU. Since PSU powers everything, it is the most important component inside the PC. Also, while the PSU warranty covers the PSU itself and you can RMA the blown PSU, the PSU warranty doesn't cover any other component the PSU fried.

 

[NDDU Julius BSIT]

Took the GPU and Motherboard with it though. I feel bad for him though. It was a high end MSI Motherboard and a Hall Of Fame Edition EVGA GTX 670. I warned him not to trust on cheap PSU but he was really short on budget and he wanted to use the PC ASAP.

 

[Aeacus]

Sad to hear it that the MoBo and GPU also went with the PSU.

Though, used high-end MSI Z68 chipset MoBo (MSI Z68S-G43 (G3), LGA1155) costs about $57 at Ebay. For GPU and at same performance level as GTX 670; a GTX 1050 Ti costs $200 (brand new) or for GPU upgrade, a GTX 1060 3GB costs $246 (also brand new).

I'd rather pay the extra $30 right away for far better quality PSU than paying $300 later for new MoBo, GPU and PSU, not to mention all that wasted time and hassle of replacing components.