amd a8-5600k Thermal shutdown problem?

[DiddlyBops]

A little over a year ago i built my first computer and I can't really remember when this started happening, but at random times (usually only during gaming) my computer would force reset itself. It wouldn't happen instantly, or even every time, but enough to be an issue, so much that it caused a HDD crash a while ago when I was just idle downloading a game. Basically I'm wondering why this is still happening since I've since changed a lot about my parts now. 

 

My first parts are as follows: 

CPU- AMD A8-5600k 

CPU Cooler- Phanteks PH TC14CS w/2 fans (their goo as well)

MOBO- MSi A88X-G43 (MSI-7793)

RAM- G.skill Ares (2x4GB)

GPU- GTX 750

PSU- Raidmax RX-535AP 535W 

 

New parts:

CPU cooler-NZXT Kraken x61 AIO (their pre-applied goo)

RAM- Corsair Dominator Platinum 16GB (2x8GB)

GPU- GTX 970

PSU- NZXT HALE82 V2 550W 80+ Bronze

 

Now normally I'd just kinda say screw it since right now I'm waiting on my new CPU and PSU as my last parts to be able to fully upgrade and be rid of this problem in a few weeks, but I'm selling all the old parts to my brother so I'd like to give him some more info on what to upgrade first so that he doesn't pull out as much hair as I have from random resets. 

 

I've yet to absolutely prove that it's resetting due to it being too hot, but I've switched out everything else i thought it could be in order while upgrading and I've used 4 different temp monitoring programs not counting BIOS (afterburner, cam, overdrive, hw). The only times the temps were inconsistent in each program was the BIOS and Overdrive where at idle BIOS says usually no higher that 40c and around 60c thermal margin in Overdrive...whereas in the other programs its around 60c idle. In cam i've had plenty of warning messages (after the reset) that say temps are over 80c so i can only assume its temp shut downs. 

 

Fortunately recently the resets have happened a lot less, but every now and again when I'm kicking ass in a game with friends and it shafts me. Keep in mind this is in damn near every game I play from intensive games like BF4 and Dark Souls 3, or "playable on a potato" games like LoL (I know I'm scum for playing LoL). If anyone can throw me some help that'd be lovely since this has been a problem for a long time now and I just wanna have a good time. Ask away for any extra details you might need to help. 

 

I love you.