Possible faulty PSU? Need opinions

[asendra]

So I have a 4 years old Seasonic g550w (80+ Gold) still on the 5 year warranty.
It has been working perfectly since I bought it with my 4770k@4.2Ghz with a 770, then a 480x and now a 1080.

TLDR
My computer freezes under load, i have to shut it down manually but then when I start it again, it lights up, the fans start running, my AIO also is running, but the computer after 5-7 seconds restarts and keeps doing the same on a loop.

After a few hours turned off, it boots ok, and under load freezes again.

Long version
I have recently changed computer cases, and also bought a corsair sata power braided cable because it has flat connectors and fits better with the back mounted SSDs.

After installing everything in the new case the computer wouldn’t boot and i diagnosed that the new sata power cable, even though it has rhe same connector on the PSU side, it is not compatible, guess corsair makes custom cables?! ... and now im using the cable that came with the PSU but the computer freezes.

Can the incompatible cable have broken my PSU?

 

[esquared]

Do you have another power supply you can install to check?

Is it possible your SSD is going bad? My computer was freezing up a couple months ago.
It was happening occasionally and I would have to do a hard reset. Finally it wouldn't boot
into windows at all. It was a fairly new 1TB SSD with 97% life left, so they do go bad.

 

[daveybrat]

Reading through a lot of reviews of the Seasonic G series power supply seems to suggest this is a common problem:

https://www.newegg.com/Product/Product.aspx?Item=N82E16817151119

 

[Campy]

PSUs are not standardized on the PSU side of the cables and every manufacturer has their own idea of the best way of doing things. Corsair have different types of cables for their different PSU lines(probably because they use different suppliers) so you need to make sure you get something that states it's compatible even if it's from the same brand.

You should never mix and match cables unless you know for certain it's compatible either from a reliable source or from checking cables yourself. Extension cables are fine because they connect to the already standardized component side of the OEM cable.

Here's a relevant video I saw recently:

TLDR; You might have damaged components you plugged the cable into, or the PSU itself.

 

[asendra]

Thanks everyone for the answers.

So, a few hours later I managed to boot up the computer. I did clear the CMOS before, but don't know if that had anything to do with it. I started to run some specific tests like memtest, also tested the hard drives, checked the windows installation for errors, malware etc.. but everything came fine. I even booted up in a Ubuntu live usb to run some test from there and still the computer was behaving perfectly ok.

So I booted up windows again and run Prime95... for 2 hours straight without problems, then Cinebench, 3DMark... and the computer didn't freeze. I tested again with OC, and still 100% stable...

So I'm at a loss now. I don't really like the though of not knowing what happened, specially if I should be RMA'ing the PSU before the warranty expires (in 4 months).

I though maybe the PSU overheated when I was trying to power it on with the bad cable and it took a few hours for it to cool down, but that doesn't sound likely..

Physically the only thing that I touched was that I removed one ram module before running memtest, but then I put it back on before running memtest again.

Reading through a lot of reviews of the Seasonic G series power supply seems to suggest this is a common problem:

https://www.newegg.com/Product/Product.aspx?Item=N82E16817151119

Huh, guess I'll be checking up on that. I though this were good and solid PSUs.

PSUs are not standardized on the PSU side of the cables and every manufacturer has their own idea of the best way of doing things. Corsair have different types of cables for their different PSU lines(probably because they use different suppliers) so you need to make sure you get something that states it's compatible even if it's from the same brand.

You should never mix and match cables unless you know for certain it's compatible either from a reliable source or from checking cables yourself. Extension cables are fine because they connect to the already standardized component side of the OEM cable.

Here's a relevant video I saw recently:

TLDR; You might have damaged components you plugged the cable into, or the PSU itself.

Guess you learn something new every day.
I've been building computers (for myself) all my life, every 4-5 years, but this was my first build with a modular PSU. I really though they were standard...