PC failing to start up

[Donny84]

Hi guys. I've been having an issue with my daughters PC.
Started a couple weeks ago where when she goes to turn it on, the lights on the fans etc turn on for a brief second as though its gonna power up but then they just stop and PC stays off.
If i try to power it back up nothing happens at all. If I switch it off by the plug and then try to power it on, it does the same brief power up before going back to nothing.

I originally assumed it was a faulty power supply so I purchased a new one which I installed yesterday, but same issue is occuring. I tried unplugging the GPU and it seemed to power up fine. So I plugged the GPU back in and it powered up fully.
Now im finding that after it's powered off again, I get the same issue and have to unplug the GPU, power up, power off, plug GPU in, power up.
Help please!
Specs below.


GPU: Zotac 1080
CPU: Intel Core i5-3570K 3.40GHz
Mobo: Gigabyte Z77-D3H Intel Z77 (Socket 1155) DDR3
PSU: Corsair CV650 Bronze - 650W
RAM: Corsair DDR3 16gb (4x4GB)

 

[Donny84]

The fact the system was originally stable then started misbehaving a couple of weeks ago indicates something is failing. As you can get it to start with the integrated gpu and have added a new psu suggests a single component is failing intermittently - but which one? The holy grail are the cpu, gpu and memory. As you can boot without the gpu that suggests your daughter's processor is ok. So it's likely either the graphics card or the memory.
Remove three sticks of memory then test them one at a time with memtest to see if any defects show up/ If non then try them a pair at a time and re-test. If still behaving then replace all four sticks and test, test and test again. (As you may gather my money is on one or more sticks of RAM). However if the memory passes all these tests then try another gpu in place of the 1080 and see if that works.
Good luck and let us know how you get on.

I should've said in the original post, but I tried 2 sticks of ram at a time in all combinations. Issue was still present.
Could the GPU really be causing this issue?
I'll try swapping it with mine in the morning.

 

[Donny84]

Motherboard Bios battery mite need replacing.

Would the battery really be causing the PC to fail on startup?

 

[Donny84]

All wires fully connected into slots, none at an angle slightly?
When replacing the PSU did you use the cables it came with or stuck with the old ones?

It's a non modular PSU so all cables are new.
I've treble checked all the cables, all OK.

 

[Donny84]

OK so, I've changed the battery, issue still present.
I've swapped the GPU and issue still happening.
I've noticed that it's now started not working when I've got no GPU in at all.
So it seems I'm down to the processor/MOBO. I may as well just get a new mobo, cpu and ram I guess... unless anyone has any other suggestions?

 

[Donny84]

Run memtest?
Get hold of a second hand cpu?

Depends how much time and effort
You want to spend on it
Compared to a few hundred quid
For new mobo,cpu,ram

I don't really wanna take a gamble on buying another CPU when it could just go to a new setup. Its an old mobo and cpu with ddr3 anyway. I'll just bite the bullet and upgrade I guess.

 

[Donny84]

Hi guys. So a little update.
I managed to find cheap 2nd hand motherboard and CPU of same models.
I have just finished installed them and while the PC is powering up every time... I'm now having a new issue where it loads to the motherboard screen which says "DEL, F9, F12, END" etc.
It just stays on this screen, pressing any of those keys does nothing. I can't load boot menu or bios.
The only thing that does anything from the keyboard is CTRL ALT DELETE to reboot PC. But it just loads back to the same screen.

Have I bought a dud motherboard or is there something I can try?

 

[Donny84]

Can you take a pic of the screen?

I assume you tried clear cmos already?

I'd pull any removable USB devices.

I don't know how to post a pic on here tbh... it basically the screen that briefly pops up on a normal load before going to windows, where you have to press delete quickly to enter bios.

I have indeed tried clearing the CMOS. Both by shorting the pins and removing the battery for 10 mins.

I've also tried removing all of the USBs, including the hard drives.

 

[Donny84]

As tetras said clear cmos/remove battery for a bit
Also think you got a new cmos battery
At some point in this thread
May as well put the new one in it

We're they sold to you as working?
Or untested?

It was sold as tested and fully working from a very reputable seller on ebay.

 

[Donny84]

When it loads to press del etc screen
Is there a flashing line/cursor/forgot the actual name of it
Top left corner of the screen?

No, its just on that screen and clicking F12 or delete does nothing.

 

[Donny84]

What are you trying to boot with/into?

Nothing. It won't even let me in to boot options.

 

[Donny84]

Think tetras means
You have a hard drive/ssd/m2 connected?
Or trying to boot off usb?
Trying a bootable usb just to see what happens
May be worth a try

I had the hard drive connected at first so should have botted up from that. Then I disconnected it and tried.
Surely I should still be able to get in to bios with not bootable drive connected?

 

[Donny84]

Yeh it's looking like another faulty mobo. I'll send it back and just upgrade the whole system. Was worth a shot I guess.