PC Won't Power On - PSU Passed Paperclip Test

Hi all,

I have a custom built PC w/ Windows 8.1, Corsair CX750 PSU, Intel Core i5-4760K CPU, MSI Z87-G45 Gaming Mobo, EVGA GeForce GTX 760 graphics card, Crucial Ballistix Sport 8GB Ram, and it will not power up. When everything is plugged in and I press the power button on the Corsair Carbide tower, it does absolutely nothing. I think I had a power surge that affected it last Friday. The computer has worked fine since 11/2013, and all of the sudden wouldn't power on after the power surge.

I started a warranty return w/ Corsair and they told me to try the paperclip test. I bridged the connector and got the fan on the PSU to spin and also a hard drive to spin. They're telling me that means the PSU works fine, but I'm not sold - I've seen elsewhere that sometimes if they're fried they can power small things but not an entire system. I've started a warranty return w/ MSI but I'm concerned it won't be the Mobo and I just wasted time and money waiting to hear that, or that they may not warranty it when they see one or two of my screws during installation slightly dug into the Mobo. Although those screws have not impacted the system in any way for 1 1/2 years, I'm worried they may blame that damage and refuse to warranty it.

How do I troubleshoot to see for certain if it is the PSU, Mobo, or something else?

Thank you,

Jeff

Edit: Using another computer to swap parts in and out to see what is or isn't working of is likely out of the question. I don't have any other PCs around and know almost no one in the town I live since I recently moved here.

Hi there,could be a dodgy power button,unplug your front panel connector from the motherboard,,should write "pwrsw" or something close to that and short the two pins with a screwdriver,lets see if its the switch's fault.

Sure,sounds a bit "ghetto" and you might be "afraid" to keep up in such a way.You can always "switch" your reset (rst) front panel connector to the "pwr" pins and hit the reset button,does it power up now?

I removed my GPU and all power except for the main 20/24 connector to the mobo and the CPU power, shorted the 2 pins to the power switch, and nothing. Tried connecting the power switch and pressing the power button, and nothing.

Hooked up my PSU to another computer and it powered right up. So, it would seem it definitely isn't the PSU. What would be the next step for troubleshooting - Mobo or CPU?

Here is a good article on troubleshooting "no start" problems PERFORM THESE STEPS before posting about POST/boot/no video problems! - Product - Systems

Article is pretty good,covering common "faults",kinda newbish,but does cover basic troubleshooting methods.I would go ahead and unplug all but necessary components,i mean all,to the last fan,and try to at least make it to a POST screen.
Give more than one try to RAM sticks,if more than one,different sticks in various slots,tell us how it goes,combination and outcome,so we can follow up,good luck!

MAKE SURE that the hard drive is plugged in and has an OS. Also, look at this if it will help at all:
How To Create a Bootable USB Disk For Windows 8.1 - TechNet Articles - United States (English) - TechNet Wiki

I read through that article and have done pretty much everything on it that is applicable. Good article, thank you.

I tried it both with and without the harddrive plugged in. It does have an OS - Win 8.1. The computer functioned normally for 1 1/2 years before just stopping w/o warning.

I unplugged everything except for the CPU power and main 20/24 pin power connections, along with CPU fan, and it would not do anything at all.

Next step, I will pull it apart and visually inspect the motherboard, front and back. If I can't see any signs of damage, I will "breadboard" like the article mentioned and reconnect everything outside of the tower, hoping maybe it was just a loose connection or a ground issue.

I'm pretty sure my mobo is toast, though

Well, is the GPU plugged in? And having just the hard drive and CPU plugged in wont allow it to do anything. Since you need ram for everything. (Except for long term storage)
Make sure EVERYTHING is plugged in correctly. Look up your case (if custom)and watch a build of it be built.

The motherboard may be plugged in wrong