Did something dumb...help

[uncfan07]

So I'm an experienced system builder but got a little too carless and forgot to plug in the CPU fan. It's an i5 7400 on an asrock b250 motherboard. I installed Windows and went to run all the updates and walked away for 15 min. When I came back the display was messed up like the picture was all fragmented. I then flipped the power switch and that's when I noticed the CPU fan was unplugged. It's the stock Intel one but with fresh thermal paste. After I plugged it back in the computer will start for a second and the fans spin then it cuts off for 2 seconds and then fans spin again. Just repeating trying to boot.

 

Wondering if it's most likely the motherboard or CPU that might have fried. I tried unplugging everything and pulling the Cmos battery, taking out the RAM but still get the same thing. 

[TheBean]

can you reach bios?

[RAM555789]

If you were running the integrated graphics off the CPU the fact you came back and the pictured was fragmented that tells me the CPU is probably fried. The CPU should have shut itself before you fried it so I would try and send it back under warranty, just don't mention you forgot to plug the CPU fan it. Just say you started to get a fragmented screen and after restarting it wouldn't boot.

[Sorenson]

Reset your cmos. if that doesn’t work unplug everything and plug it back in. Intel chips have safety shut offs so I can’t imagine it fried itself.  

[uncfan07]

So my wife's computer has a G4560 so I swapped CPUs and the 7400 booted just fine in her computer. But when I put the g4560 in the new one I got the same thing, fans spin then stop nonstop.  I'm guessing it's the motherboard then. Luckily I got the board from Amazon so should be an easy return

[uncfan07]

I find it odd that a i5 7400 would have somehow messed up the board by just not having the CPU fan plugged in. The case has 2 intake and 2 exhaust fans so I know it was pretty cool. How hot could it have gotten

[Rosss]

I mean it's not even clear that it was your fault tbh :P.. 

 

My 2 yr old laptop just had the same problem btw, display all messed up, then troubleshooted to probably be motherboard or ram. I'm trying to get it repaired with extended warranty so gl me.