Question Nothing functioning after changing cpu but there's power!

[michaelt76]

Hi, I know I mentioned cpu but I think it might be a motherboard problem. Power goes into the motherboard, the red power logo light is lit up on it but pressing it does nothing, no fans just nish like power isn't reaching anything. Pc worked fine before and the cpu swap went without bother. I've taken cpu back out to check the pins and they are fine. I've unplugged all leads from the psu and everything else and replaced them.
I've built a lot and never encountered this, I'm crap with the electronics part of it!

Anyone any idea what on the motherboard could cause this?
Could the psu suddenly breakdown but still be pushing some power out?

Thanks

 

[sizzling]

Have you tried the old cpu again?
What exact motherboard and CPU’s are you using?

 

[michaelt76]

Yeah I tried the old cpu again. It's 1150 cpu a 4790k. It's a Asus z87 pro, psu ax750. Worked fine for years. Bought cpu from ebay it came in a wet bubble envelope on its own with a bit of antistatic wrapped around it. I'm blaming it on him but yeah I tried the old cpu which worked 10 minutes before swapping it. Never had a problem with the computer since 2014.

Can cpu problem stop everything from working, I always got a boot error with bad cpu not complete shutdown!

I'm taking it to pieces and it's custom watercooled so a 5 minute job has turned into hours of f'ing fun!

Just looked at the cpu I bought under a lens and it's covered in crap which has got onto some pins. I couldn't see it on the pins until a closer look!

Thanks

 

[michaelt76]

Got the stuff on the pins off, no pins are bent, cable ties come in handy for more than just tieing cables!

Would a problem on motherboard or cpu stop the psu fan from spinning?

 

[sizzling]

Have you updated the BIOS to one that supports that cpu?

 

[michaelt76]

Thanks for taking your time to help it's appreciated!
The first cpu in this system was a 4790k back in 2014 so that isn't the problem but that wouldn't do this, the psu would still power up. I was building custom pcs for years as a job and come across a lot of problems but this had me stumped because everything worked fine then didn't.
It's a power problem I just didn't know what but now I think it's the psu. I've just done the paperclip test on it, there's the usual click, the fan starts then stops. I click the off switch, another click for power off then the fan spins again. There's been some damp in the air in my flat so I put the psu in front of an heater. After half hour I tried again and now it stays on for longer.
This psu cost a bit and custom blue braided cables were £100 alone so don't want to give up on it. The aesthetics are gonna be all wrong, I spent grands on this system, a lot extra so it would look good so shabby non modular plastic would kill it#

Just started a open uni it degree so a crap time for this to happen!

Just realised I'm typing like a cracked would... in abundance... no I'm not a crackhead!