PC restarting repeatedly, eventually boots.

Loony BoB

Loony BoB

Loony BoB

Associate
Joined
10 Mar 2007
Posts
235
After shutting down my PC, it has started booting for about 2 seconds, fans and lights, then effectively restarting over and over until eventually it boots. The main thing I note is that when it DOES boot, that's then the LED codes start popping up on the Gigabyte board - before that there's nothing on the code display at all while it's rebooting constantly.

Unplugged drives and graphics card, still happens. Tried new power supply, still happens.

I'm unable to easily remove the RAM due to the cooler being smack over the top of them, but that's going to be my next hopeful fix - after that I know I'm looking at the system board or CPU. Any thoughts on how best to diagnose which one it is? Both are still under warranty (three months shy of three years old) but as they're obviously with different manufacturers, I've no idea which one to go to!

Tempting to just go for a Kabylake 4.2GHz and grab a new mobo but I have to remind myself that the stuff I have is still very good spec and in warranty... but... urgh spending time without a PC would be murder. At the moment the PC is still at least eventually booting, and if I never shut it down it's fine. But yeah. Any advice is welcome!

EDIT: Should probably note that I hadn't changed anything on the PC around the time this started happening, so likely a faulty item rather than a setup issue. But happy to be proved wrong!
 
Last edited:
Complete spec?

Also have you tried clearing the CMOS and loading optimised defaults (was it clocked?) and double checking all connections - even kettle lead at the back of the machine.

If using an extension lead - try wall socket or different, quality, extension lead (garden/DIY one would be good for test purposes).

Loony BoB said:
I'm unable to easily remove the RAM due to the cooler being smack over the top of them
Click to expand...

*next list of tests will involve 1 stick of memory eventually if the above doesn't yield results...
 
Not overclocked (I know, I know... I'll figure it out someday... maybe). Will clearing out the CMOS still help with that in mind?

Tried a new outlet + power cable (completely different room), no change.

Gigabyte Z97X-Gaming 7 Intel Z97 (Socket 1150) DDR3 ATX Motherboard
Intel Core i7-4790K 4.00GHz (Devil's Canyon) Socket LGA1150 Processor - Retail
500GB SSD, a few older drives
EVGA 750W psu, Gold 80
Alpenföhn Brocken ECO CPU Cooler - 120 mm
16GB RAM, unsure of spec
Gigabyte GeForce 980
Bunch o' fans and a box.
 
Nothing jumps out - and the fact it wasn't clocked rules one factor out of the equation.

Have you tried clearing CMOS, checking cables and different socket?

Conversely, you could unplug all the drives, peripherals etc...
 
Checked each stick of RAM in DDR4_1, one at a time, no change. Haven't got to CMOS yet but thought I'd post this as it's the first time I've seen it. Most of the time it's just doing the whirring of fans then restarting in a couple of seconds, but then there was this on one occasion...

https://youtu.be/Kpc3nlwuxQo

Apologies for filming vertically ;)

EDIT: Working on CMOS now. The eventual restart just isn't happening for me so will do it on the board.
 
While your testing - i would keep the other 3 sticks removed and add them once/if you gain stability.

I'll wait for your CMOS reset - may involve a flathead screwdriver (bridging the gap between 2 pins).
 
Next step would be strip it down to a skeleton setup:
  • CPU
  • memory
  • Onboard GFX
Remove, unplug, everything else (drives/cards etc... - you only need to unpleg drives/sata and power connectors. You will need to totally remove the GFX card :/) - and see if you get any signs of normality.
 
Loony BoB said:
Already done that exactly earlier, no dice. =/ Thinking at this point it may just be a rather dead SBD/CPU :(
Click to expand...
Do you have a spare PSU?

And did you get to move all the memory - and try alternate slots?

Is there any visible warping around the CPU socket - you could try slackening the screws around the cooler (within reason) or try stock cooler (a PITA i now) as this sometimes can cause issues (although yours isn't that big). Especially as you have all 4 dimm slots filled.
 
Yeah, used a new PSU (Had to buy one for the girlfriend's rig anyway) and it didn't make a difference. I did remove all the memory and tested them one by one with no difference.

Read up a few other threads on various forums and in two of the cases it was a RIP CPU. Looking like that might be the same for me. :( I'll make attempts to clean up and redo the CPU and cooler once I find my alcohol but outside of that, I fear I'm out of options.

So... how are those Kabylake 1151? :')
 
Loony BoB said:
Read up a few other threads on various forums and in two of the cases it was a RIP CPU. Looking like that might be the same for me. :( I'll make attempts to clean up and redo the CPU and cooler once I find my alcohol but outside of that, I fear I'm out of options.
Click to expand...
Could equally be motherboard - hard to know. But doesn't look good from your diagnostics :/

Loony BoB said:
So... how are those Kabylake 1151? :')
Click to expand...
If it was just a motherboard that you needed i would stick with what you have as it's still a very capable system.

If you're after a new platform have you considered Ryzen?

EDIT: Last resort - I would try setting up the system outside of the case - skeleton setup - to rule out shorting. Start the system by shorting the pins.
 
Excuse me for being an idiot: What is it that would cause a BIOS to get borked? :o Isn't it safe from the start to finish, provided you don't change hardware?
 
I had the same board and CPU and had a very similar sounding problem a month or so ago (check my post history). Didn't solve it, worked fine with any other CPU in, and the 4790k worked with other systems, but never together.
 
Decided to give up fault finding as I'd tried everything. Sold the CPU to a mate, he's had no probs with it, got a refund on the board. Built a temporary system with one of the cheap Z170 board deals floating around and picked up a second hand i5-6500 to tide me over until the dust settles on the Coffeelake announcement.

Not had any issues since, only changed the MB, CPU and RAM, everything else I kept.
 
You must log in or register to reply here.
Back
Top Bottom