Question New build, 2nd CPU ordered in a row that wont work

Sep 29, 2019
Hello everybody,

recently i have built 2 new PCs with the following specs:

OS: Win10
MoBo: GiBy Z390 Gaming X
CPU: i7 9700KF
RAM: G. Skill Ripjaws V DDR4 32GB
GPU: Nvidia GeForce RTX 2070
PSU: be quiet POWERZONE 850W

the only difference between them are components like SSD and HDD and DVD Drive but I've tested them all and found out to be working fine.

The thing is, one PC works and the other not. I found while I conducted my 1st testing, it was the CPU. (Clearly because I tested everything else and was working well on the 1st same specs PC and on the second as well). So I exchanged the CPUs and then the other one was not functional while the latter was. So I returned he CPU to be exchanged with a new working one. The new CPU that came in worked for about 5 hours and then after a while gaming the PC started giving me some BSODs, if I remember correctly some are supposed to have to do with drivers, f.e. ''Driver overran stack buffer'' and then I tried to use automatic repair, but it kept giving me BSOD and eventually wouldn't pass the point after BIOS while loading OS or trying to install win10 without giving BSOD. So I changed again the CPU from the working PC to the failing one and it worked just fine for an hour or so which convinced me it was the unlikely scenario of a 2nd CPU coming in damaged...

Additional info of interest could be that I didn't OC.

Does anyone have an idea if there could be a reason why the CPUs are failing or should I trust this simple testing of my own? Could it be a faulty Mobo? Or settings I wouldn't know of?
My next plan is to use the new CPU that will come on the already working PC and the old tested working CPU I already have on the PC that is suffering this issue and hopefully it won't work for 5 hours and fail...

Thanks for any suggestions that could have to do with my problem.