Faulty PSU or motherboard, or neither?

cosmicpalantir

Commendable
Oct 8, 2016
2
0
1,510
Hi everyone. I recently bought a new computer case and PSU, with the intention of upgrading some other components at a later date.

However, when using my new PSU, I get a "no signal" error in the display. My instinct is that this is an issue to do with power to the motherboard. My old PSU has a 4-pin power cable, whereas the new one has 8, so I split it in half and just used 4. Everything that is running (cpu fan, case fans, HDD) still runs when I unplug this 4-pin power cable, so I guess they make use of the larger power cable?

Just to clarify, it's working fine with the old PSU in the new case.

Specs are:
Motherboard - Gigabyte ga-p35-ds3l
Graphics - Zotac GT630
Old PSU - Casecom ATX 450W
New PSU - Corsair CX750M 750W
Do you need any more info?

What I'd really like to know is whether the community thinks this is a problem with the PSU, or whether plugging half of an 8-pin power connector into a 4-pin motherboard socket can be dodgy? Or.. if I'm barking up totally the wrong tree and there's something else. I've ordered a molex to P4 cable to test whether that works.

Finally, I want to mention that only half of the fans are powering on, but I'm almost certain that's a different issue.

Thanks!!
 
Solution
My best bet is that your Tier four Corsair PSU is to blaim.
PSU tier list: http://www.tomshardware.co.uk/forum/id-2547993/psu-tier-list.html

Refund the Corsair and get a Tier two PSU, preferably Tier one if you could afford it.

I suggest Seasonic M12II-750 EVO (80+ Bronze, fully modular, Tier two)
specs: https://seasonic.com/product/m12ii-750-evo/

Or a better unit, Seasonic X-750 (80+ Gold, fully modular, Tier one)
specs: https://seasonic.com/product/x-750/

Aeacus

Titan
Ambassador
My best bet is that your Tier four Corsair PSU is to blaim.
PSU tier list: http://www.tomshardware.co.uk/forum/id-2547993/psu-tier-list.html

Refund the Corsair and get a Tier two PSU, preferably Tier one if you could afford it.

I suggest Seasonic M12II-750 EVO (80+ Bronze, fully modular, Tier two)
specs: https://seasonic.com/product/m12ii-750-evo/

Or a better unit, Seasonic X-750 (80+ Gold, fully modular, Tier one)
specs: https://seasonic.com/product/x-750/
 
Solution