Solved Black screen and sound loop crash requiring reboot

Edit: My PSU died, so I assume that was the cause of the issue this whole time, a half functioning power supply.

This issue occurs whether I am gaming or not, but gaming causes it to occur more often. In fact, my pc crashed typing this post so I'm currently rewriting it all.

When I go to reboot the computer, I notice CPU fans 1 and 2 (top/back) are off. I'm not sure if that means anything, but yesterday I had to reseat my GPU/ram etc. to get my computer bootable due to this issue. I'm not really sure what to do, I've tried many things. I've had this black screen issue for months now..

RAM is fine, memtest doesn't detect any issues. I have tried using only one of the ram sticks at a time as well. I have tried reseating the GPU, putting it into a different slot. Newest GPU drivers. Temps are good, all under 40 idle. Tried Windows 7, Windows 8. HDD and SSD. Making sure all the PSU cables are fully in their place, along with every other cable in the PC. Have taken out all of the PC parts out and rebuilt my PC. Booted PC without CMOS battery. Installed a mobo speaker, and all is normal there. I've tried using the other GPU video headers.

Furmark gets my GPU to 82c under maximum load. My cpu I believe gets to 64c. I can't find any memory dumps, since it's not a BSOD. But I could potentially be looking in the wrong places, Event Viewer only tells me that the PC turned off unexpectedly.

I'm thinking of sending the GPU to MSI, it's still good for warranty and all but I don't even know what exactly is causing this weird issue.

Please run hardware diagnostics you haven't done.
Also make sure your drivers are updated.

Okay, I've spent lots of time diagnosing my issue.

Can't be the ram that's the issue, since my PC still crashed with different ram sticks.

I switched the PSU out and am currently using it on my other PC along with the ram I had on my PC, I haven't crashed at all.

I switched the GPU's out as well. It's clearly not my GPU (R9 270), since my GTS 450 also black screened on me.

I've tried using a different wall outlet too: my PC still crashes.

It has to be either my motherboard or my CPU, I'm guessing. I've done some prime95 and memtest. Prime95 gets my CPU to around 61c max and I haven't crashed from it. Memtest doesn't find errors in my ram, and furmark gets my gpu to 81 - 85 (85 is the max good temp for my gpu, according to MSI).

How can I know if my motherboard is dying? I've inspected it. No blown capacitors or anything. It is an ASROCK 970 Extreme3, which I now hear is bad.

Only way to find out if your mainboard is the problem is to replace it, I haven't seen a way to test the mainboard.

Well, now my PC won't turn on. Three CPU fans simply won't turn on. I get no beeps from my mobo speaker. I've just now put my PC completely back together after disassembling it to see if that does anything.

My front case fan works, as does my GPU's. My hard drive seems to be on as well. Any ideas?

My PC was working perfectly for about a week after disassembling it and putting it back together. Then a few days ago I decided to oil my cpu fan since the bearing is making lots of noise, then my black screen issue came back! After a few times of the black screen occurring, the PC stopped turning on. Top fan (above CPU), fan in back of PC and the CPU fan itself are the fans that don't turn on at all.

My PSU works in my other PC though so it can't be that right? Could it be the CPU, possibly? There's a small amount of thermal paste on the fins of the cpu..