PC powers off and on at night (12am)

[Phil1503]

Hi,

since a few days i have a weird Problem. My PC is turning the power off and on randomly at night. It just happens after 12am and stops by i would say around 5am or so? During the Day nothing happens, no matter what i do or run?!

Steps i took so far:

Tested Memory,GFX,HHD and CPU (Stress Tests)
Checked all Temps frequently
Run a Virus and Malware Scan
Cleaned Registry via CC-Cleaner
Set Windows 8 to High power Plan and made sure nothing get turned off or put to sleep at any time
Set Windows 8 to show me a Bluescreen instead of just restarting

Nothing helped so far. Its not Rebooting! The power is turned off and then immediately back on, it reboots and doesn't show any errors, like nothing happened?

My System is based on a XPS 8500. 3 Month ago i changed the GFX to a GTX960,the Hard disk to a 120gb SSD for Windows and a 1TB WD for data like Games. I also changed the psu for a 750w Modular one.

Anyone has an idea?

Thanks

 

[X79]

What's your PSU make and model?

Turn off wake on LAN too.

 

[Phil1503]

Cosair CX750M

I also checked wake on LAN and its off

Thanks

 

[X79]

You'd better hide before someone comes in here and pounces on you for using a Corsair CX.

http://www.tomshardware.co.uk/forum/id-2547993/psu-tier-list.html

 

[Phil1503]

? Well i have not the time yet to go thru that whole posting, so would you mind to tell me what ya mean? Is my PSU the reason for this weird error or is Cosair just not good anymore? It was all Best Buy had and i needed one that day and know Cosair as a Brand...

 

[X79]

It's quite possible, that's all we can say. The CX lineup is said to be low quality. The Corsair AX line is better, as per the list.

 

[Phil1503]

Well i might be in this list and might also be true (i used comp since many years and never cared were a transistor was made) but i honestly don't think its the PSU. I mean... just at night? Between 12am and 5am? Does it have a timer? Its not heat.. i live in California and if the PC makes it thru the Day without then well, its not Heat

Thanks for your suggestions so far!

I hope someone had this before. Maybe its some weird windows setting?