# Mysterious PC Power up issue



## Tanuj Tiku (Jul 29, 2013)

I have been facing a very mysterious issue with my PC since a couple of weeks.

I have the following specs:

Intel Core i7 3930K, 6-Core overclocked to 4.2 Ghz by an expert which runs at max 50 degrees at 100% CPU usage.

ASUS Rampage IV Motherboard

Corsair high-end 850 PSU

Kingston 4GB RAM Sticks - 32 GB

SSD for boot up and projects. 

It started a couple of weeks back and we are all stumped here. I have never experienced anything like it.

Basically, if I keep the PC switched off for more than a few hours (ball park figure), it does not power up for the first 20 mins. 

I keep pressing the power button but nothing happens. The motherboard is all lit up. 
The PSU is brand new and has been checked in another computer.

Once it powers up, everything works fine. 

But it wont power up for sometime if it has been switched off for a longer time.

we changed the batteries on the board, we even kept the power going to PC and also drained it many times.

If I restart immediately it works but if i leave it off for a few hours, it wont boot immediately. The fans wont move - nothing.

No errors reported on the motherboard. I am running this off an APC UPS which is at minimum load. All other peripherals work fine.

I tried connecting it to a different power source - same thing. 

Another PC in the room works fine. Everything else, including the AC, 46-inch LED TV, my monitors - everything works.

The PC works just fine once its powered up. The GPU is fine as well. System performed all tests as expected. 

There is no moisture issue because even if its left off in the AC, it still wont boot up immediately.

Any thoughts about what this could be? Anyone else faced this problem with this motherboard?

I am going to replace it anyway once I finish my ongoing project. For now, I cant loose any time and I am just running it 24/7. I will get some down time end of next week.


I am just curious as to what it could possibly be? 


Tanuj.


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## JFK (Jul 29, 2013)

On my computer, if my G600 is plugged in at boot the computer will hang at post screen, unless I hit F12 or Del to enter menus. 

I accidentally discovered that my mobo has two USB 2.0 ports on the back that are NOT powered @ boot. Plugged into one of these, my mouse isn't powered until Windows boots and everything goes smoothly. 

In your situation, I'd definitely unplug every peripheral and try booting. This type of thing can be cause by certain drives too. Start from the ground up: unplug all the drives too, see if the problem persists.


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