[SOLVED] PSU expert help needed!

winwiz

Distinguished
May 13, 2009
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A few days ago I purchased a second hand budget gaming pc:
Xeon e5 1620 cpu
Lenovo s30 mobo
32gb ddr3
256gb budget samsung ssd
Palit gtx 1060 3gb
Corsair cx750 psu

The pc randomly restarts if I run heaven graphics benchmark for 30-60 minuts.
If I decrease nvidia power slider to 50% heaven runs all night.
Prime95 cpu test runs fine.
So im guessing the reboots are caused by the gtx 1060 or the corsair psu.

So I swapped the psu with a ocz from my main pc (amd 5800x3d + rtx 3060ti)
But the second hand budget pc refuse to start with my ocz psu.
If I press the power button for a second or two the fans will run and the lenovo mobo displays post code 00
No video signal or anything.
I have double checked that 24pin and 4pin cpu connectors are indeed connected correct.
I have build pc computers over 20+ years but have never encountered a motherboard that refuse to boot with a working psu. So this really puzzles me.
Anyone know what could cause such behavior?
 
Solution
Turns out the lenovo s30 mobo has two 4pin power connector.
One connector is located below the cpu socket and the other is placed at top of the board.
So I forgot to connect the one in the top because it is hidden behind a case fan...

winwiz

Distinguished
May 13, 2009
26
1
18,545
Turns out the lenovo s30 mobo has two 4pin power connector.
One connector is located below the cpu socket and the other is placed at top of the board.
So I forgot to connect the one in the top because it is hidden behind a case fan...
 
Solution