PSU broke, PC powers up but no signal to the monitor

[Defrosted]

Hello.

The situation is as follows: near the end of last week, a burning smell started arising from my friends PSU and it felt hot to touch. After shutting down the PC it wouldn't boot again, the power went on for a few seconds before passing out. After a little tinkering he had managed to get it to start up again, but no signal was received by the monitors.
As I live in a different city, I sent my old PSU by mail, but it didn't help much. Sure there isn't a burning PSU anymore, and the PC starts up, but still no signal.

At the moment I'm suspecting that the PSU might've broken some other components, but it's hard to pinpoint which. The GPU isn't the primary problem the very least, since the motherboard's integrated GPU won't give out a signal either.

I asked him to do the following after receiving my old PSU, which had no impact whatsoever:
- Checked that all contacts and wires are fine
- Clear the CMOS from motherboard (also between tinkering with the memory/GPU)
- Removing the GPU and attempting to get a signal from the integrated one
- Removing one of the memory sticks and after testing that, switching the other one in (I checked the appropriate slots for the sticks from the manual)
- Unplugging the PSU and pressing down the power button on the PC case (I doubted this method I found by Googling, but gave it a try just because we were that desperate)

The motherboard doesn't have one of those "screens" showing errorcodes / digits. The board didn't come with a speaker either (that beeps codes during POST). The PC has been in use for at least a year without any problems. What are the chances for warranty in the case of broken components?

PC Specs:
PSU: Corsair CX750M (original), my old one is Nexus RX-8500
Motherboard: Asus Z170 Pro Gaming
Processor: Intel Skylake i5-6600K
Memory: 2x HyperX Fury DDR4 8Gb, total of 16Gb
GPU: Asus Strix GTX 970

Hopefully someone could help us, since we're running out of options as to what could we try and what might be broken.

Thank you,
Defrosted

 

[DRagor]

Tell your friend to get and install motherboard beeper. Then go to minimal build: just mobo+CPU+PSU, no drives, nor ram, no GPU, no usb devices. If he gets no beeps at this stage, either CPU or motherboard suffered damage.
And I see no reason that warranty would not cover such damage. It's not any kind of mechanical damage or user's fault after all.

 

[Defrosted]

The beeper is still in the mail, but we'll try what you suggested when it arrives. However, my friend tried to plug his old PC in to the two monitors and it gives no signal either. He checked all the connections and cables. There's a possibility that GPU could also be fried as he tried getting an image from his current setup that is the problem PC, but this sounds a bit sketchy..

Edit: Apparently one of the RAM in his old PC was damaged, he's getting a signal and a successful boot now. At least the GPU wasn't fried.

 

[Defrosted]

Update: My friend finally got the beeper. It beeped to signal that no memory was attached without anything plugged in to the motherboard. When he tried to plug in the RAMs to any slots in any configuration it gave the same beep error every time. This suggests to me that either both of his RAMs are dead or his RAM slots/Motherboard are dead. That would also explain the symptoms. We will try to find out if he could test his RAMs in another PC, but none of his or my other friends in the area has a motherboard that supports DDR4.

 

[DRagor]

Make sure you put ram sticks fully into the slot, until both locks snap into place, it's common error.
If you can test the ram in another motherboard, do it. If you can't, note that normally probability of 2 sticks going dead is lower then motherboard going dead. However, in this case, considering it was PSU going down, you have to prepare for the possibility that both motherboard and ram got damaged.

 

[Defrosted]

Finally an update: The mobo and PSU went through the RMA process and he now has new replacement components. The RAM were fine. CPU is presumably fine since the PC boots now and the mobo also gave error beeps. Yet he's still not getting a signal to his monitors. We're now thinking if there's a way to get his GPU tested. We tried the integrated graphics but no signal there either (the GTX was unplugged obviously and we tried clearing the CMOS even though the BIOS should be in factory settings).

 

[DRagor]

Since there's no display neither from motherboard or GPU, there must be another reason for no display problem (although that does not mean that GPU is surely good). Again, check just mobo+CPU+ram, no other devices. Failure to show display at this point would strongly point toward CPU failure.

 

[Defrosted]

He has tried everything, including just having mobo, cpu and ram plugged in and no signal. He can't test his CPU by himself so he's just going to RMA it and take the risk. If it isn't dead he has to pay for its transportation and a handling fee. There always is the chance that the new mobo could be dead-on-arrival.

 

[Defrosted]

Another update: it's most certainly the CPU that's dead. He said that he took it off again and now noticed that the corners of the chip had "bent", which probably had already been earlier but he just hadn't noticed. He sent me a photo of the chip and it definitely looks like it has taken some heat damage or something, as two of the corners look like they've "collapsed". Image: http://i.imgur.com/Ub432LQ.jpg, the corners are the right top corner and the corner nearest to the camera.