New PSU not powering up

Denecc1

New Member
I recently upgraded my computer with a brand new motherboard,CPU & GPU.
I purchased a new PSU as the one I had would run the fan but not turn on the screen & accessories. We are trying to install the new PSU but it won’t seem to turn the computer on, it just lights up the motherboard but doesn’t turn on the fan.
I’ve checked the pin, used the new wires & checked that everything is connected right. The new PSU is the Gigabyte P750GM.
Please help!!!
 

johnb35

Administrator
Staff member
Do you have the 24 pin main and the 4/8 pin cpu power connector attached to the motherboard?
 

johnb35

Administrator
Staff member
Did you install the standoffs correctly between motherboard and case? It's very possible that the old motherboard doesn't have the same screw holes as the new one and if a standoff is touching the motherboard where it shouldn't then it won't boot.
 

Denecc1

New Member
So just removed the mobo and reinstalled everything to make sure it was all done correctly as you mentioned. Still won’t power up :(....any other suggestions?
 

DavidG

Active Member
It doesn't sound as though the PSU is the problem - Post the details of the Motherboard, CPU and RAM . You could also try removing all but one stick of RAM and seeing if it will boot, if possible try each stick of RAM one at a time to see if you have a faulty stick preventing it booting
 

johnb35

Administrator
Staff member
Are you sure the metal standoffs are in the correct places. Most times then not this is the problem. Sounds like there is a short going on
 

Denecc1

New Member
Mobo- B450 Steel Legend ASrock
CPU - AMD Ryzen 3 3100
RAM - Trident Z RGB- DDR4-3200
All 3 items are brand new/never used from the store.
Tried removing the Ram as mentioned as well. No luck.
 

DavidG

Active Member
Bad news I'm afraid - you need a BIOS update
Check on the box and see if it has the BIOS version listed - you need a BIOS of at least P3.20 released 28/11/2019
BIOS Support link

CPU support list
Unfortunately as you are in a no boot situation you need a different CPU to do the update. Probably the best situation is to return the board to the vendor or Asrock and ask them to update it for you. Partpicker does warn of this potential incompatibility and the no boot in this situation is well known.

Unable to Boot New Desktop System Configured with AMD 3rd Generation Ryzen™ Desktop Processor, and AMD Socket AM4 400-Series Motherboard
 
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Denecc1

New Member
Hey everyone. So we moved the graphics card to a lower PCI slot and that seemed to do the trick. Has been working perfect. Thank you everyone for your help.
 

StrangleHold

Moderator
Staff member
Something is still not right if it isn't booting on the main PCIe slot. Look around in the bios and see if it has a setting that sets the boot slot.
 
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