Computer shut off unexpectedly....won't power back on but LEDs will light up?

[onetrickdave]

Hello,

I recently built my first PC to use as a HTPC (this website has been massively helpful during the process, so thanks for your knowledge!) and while watching TV last night through Windows Media Center my PC unexpectedly shut off. After a couple minutes of pure panic trying to turn it back on again, it finally booted and ran normally before I shut it off about 5 minutes later (including rear power switch).

Today I went to boot up and when I turned on both the rear power switch and the power button, nothing happened aside from the LAN light and the power button LED will light up along with the fan lightly spinning on the PSU. I've gone through the checklist posted on this site but I still can't pinpoint what is going on here. My gut says it's the PSU but if that's the case why am I getting lights on from the motherboard? And would the fan be spinning at all?

Any help here is greatly appreciated and thanks in advance for your assistance!

Specs:
CPU- Intel Core i5-4670K
MB- ASRock Z87 Pro4
GPU- GTX 760
PSU - Corsair CX600
RAM - G.Skill Sniper series 1866 4 GB (x2)
HD - Sandisk 120GB SSD 2.5"
CPU Cooler - CM Hyper 212 Evo

 

[chrisso]

Try taking one ram stick out, reset the cmos and fire it up again.

 

[onetrickdave]

Try taking one ram stick out, reset the cmos and fire it up again.

I did the one ram trick to no avail previously but forgot about resetting the cmos. I did just that and it booted right up. thanks for your help!