Instant shutdown after laptop turned on


Dec 5, 2012
I just bought this laptop, it's a Gigabyte p55k. First off it takes forever to start windows and after it logs in the screen is just black with the mouse, I can ctrl shift esc to bring up the task manager so i'm just guessing explorer is taking forever to start. But that isn't my main problem.

So after my laptop has been powered off overnight or for some long period of time the first time I turn it on no matter what I do about 10 minutes after powering it on it will instantly shut down. Doesn't matter if I leave it idle, browsing the internet or playing games. Then after I turn it back on it wont turn back off until I leave it off for a while.

I have checked the ram using windows memory diagnostic and it stalls at 21% for hours then lags when I go to options. I checked it again with memtest86 and it did 6 passes with no errors, the test took about 11 hours so I don't know if that is normal or not.

I did a HDD test it's passed all the windows programs chkdsk etc and crystaldiskmark came up with this
CrystalDiskMark 5.1.1 x64 (C) 2007-2016 hiyohiyo
Crystal Dew World :
* MB/s = 1,000,000 bytes/s [SATA/600 = 600,000,000 bytes/s]
* KB = 1000 bytes, KiB = 1024 bytes

Sequential Read (Q= 32,T= 1) : 112.528 MB/s
Sequential Write (Q= 32,T= 1) : 79.592 MB/s
Random Read 4KiB (Q= 32,T= 1) : 0.699 MB/s [ 170.7 IOPS]
Random Write 4KiB (Q= 32,T= 1) : 0.716 MB/s [ 174.8 IOPS]
Sequential Read (T= 1) : 85.984 MB/s
Sequential Write (T= 1) : 86.402 MB/s
Random Read 4KiB (Q= 1,T= 1) : 0.254 MB/s [ 62.0 IOPS]
Random Write 4KiB (Q= 1,T= 1) : 0.639 MB/s [ 156.0 IOPS]

Test : 1024 MiB [C: 18.7% (170.8/915.9 GiB)] (x5) [Interval=5 sec]
Date : 2016/01/25 21:39:17
OS : Windows 10 [10.0 Build 10240] (x64)

So at this point I don't know if its my RAM, HDD, mobo or what. Any advice would be helpful