Help pls..Faulty memory or mobo?

[VerVistas]

Hey there. 

For the past month an a half I started getting kernel power errors that crash my pc on random occasions, either while gaming, watching YT videos or while in desktop.It freezes for 10-20sec and then restarts, without any blue screen. I did what I could software whise, (clean windows install, change power settings, fast boot off, update drivers, etc) to trie to solve it but it didn't help. So I think It should be a hardware problem. Either ram or motherboard maybe, since I can stress gpu and cpu fine, and because of that I also don't think is psu problems. The thing is, I'm having trouble figuring out what it is. I left the pc in a pc store to diagnose it and they said it had alot of errors in ram. After I bring it home I changed the ram from channel A to B (Dual channel) and did the test again with memtest86 bootable. The first test took about 2.30h and I had an error on stage 7. After that I repeated it and left the pc doing a test for 5 hours, and it finished it without any error... Could that indicate that the problem is with my motherboard?  I will trie to change the memory to channel A again and repeat the test to see..

I have the latest bios and most recent drivers and my windows installation is recent. Also I don't have temp problems. This problem has been so anoying.. Any help or tip would be nice. Thanks

My specs are: 

- Gigabyte x370 gaming k5

- Sapphire RX 580 8gb

- Seasonic S12 II 520w 

- Ryzen 2600x with artic freezer 33 esports one (No OC)

- Corsair vengeance Led 3200mhz(2x8gb)  currently at 3066mhz ( It runs stable since last bios update at 3200mhz at stock voltage but I lowered it to see if it would help)

 

[SpookyCitrus]

If memtest is saying the ram has errors and it was professionally diagnosed as having bad ram, replace the ram...

[VerVistas]

But I repeated the test to send a pic of the errors to corsair and it has no errors.. In the meantime the error is not occurring. I've bought another ram to test also. 

[VerVistas]

Take a look at this test... Finally after 3 tests one of them with only one error I got this one.  I think is safe to say my memory is done..But why are the tests different every time I do it?