Question PC games crashing more than before upgrade HHEEELLLP!

Jan 22, 2021
Hi Guys, i'm pretty new to PC gaming, well i say i am, its my son that does the gaming, i just try and keep everything running, but still i am new to all things PC.
I have upgraded components in my sons pc but he keeps getting crashes on various games, Fortnite regularly, Forza H4 won't even load to the game it crashes on the intro, apex legends also crashes a lot, even minecraft wont run properly. I realize this means nothing without specs so here goes:

Original pc

i7 -870
Gigabyte mobo (can't remember model)
16gb hyperx blue 1600mhz DDR3
GTX 970
600w PSU unsure of brand
2no. 1TB HDD's
Windows 10 Pro
3no. 22" 1080p monitors

Games played ok on this, Fortnite had loads of lag but did not crash, Minecraft was fine, didn't have forza, Apex was fine just a bit of lag.


Ryzen 7 3700x
Asus Crosshair vi Hero mobo with latest BIOS
16gb Hyperx Predator 3200Mhz
Zotac GTX 1080 amp OC
Same 600w PSU
M.2 512Gb SSD
Fresh install windows 10 pro
2no. 1TB HDD's
3no. 22" 1080p monitors

Note: all upgraded parts are second hand from ebay, however, other than for games, they all seem to be in perfect working order.

During the upgrade i wiped one of the HDD's and then moved all of his files (pictures, videos, clips, Minecraft Worlds etc...) on to it.
I did fresh installs of all of the games (some onto the SSD and some onto the HDD) and installed all the latest drivers for the mobo and gpu etc...
With most games he got all his progress back when he logged in so we thought all was good.
I have plugged the original HDD back in with the old Windows and games still on it ( i can actually still boot into this old windows from the BIOS, which was handy for retrieving data for some of his games) but it is not used other than acting as a backup if anything goes wrong.

everything seems to run fine, i've done various system scans, stress tests on the CPU and the GPU and also tested the memory with the windows tool (can't remember what its called) and found no issues, in fact it all seems to run flawlessly.

Then we get to the games, Fortnite just randomly crashes, it just freezes and states there has been a problem and needs to close, then sometimes it closes and other times it just stays on the screen and has to be forced closed from task manager. I have uninstalled and re-installed this many times including the epic games launcher.

Forza Horizon 4 will not get past the house on the intro, it just closes with no error message. Again i have uninstalled and re-installed several times, no change.

Minecraft loads ok but as soon as he starts playing the picture completely moves on the monitor down to the right hand corner so only the top left hand corner of the game can be seen, and it flickers from here back to the full screen constantly which makes it unplayable.

Apex i believe is similar to Fortnite in that it just randomly crashes.

Warzone regularly crashes and he gets Directx error message. I will try and get a screenshot of this for more details.

Fifa 20 he gets an odd error message saying that the GPU has been physically removed (which obviously it hasn't), again i will try and get a screenshot of this.

He also likes streaming and editing vids for his youtube channel (which is why i went for AMD) which all runs great, but is obviously a problem when the games keep crashing.

Its driving him, and more importantly, me nuts as i have done loads of research and tried alsorts but nothing seems to work. Being a complete noob to PC's i thought upgrading the system everything would run better and smoother and i would have a more peaceful life (palm hitting face very hard) oh how wrong i was.
So, to all you clever bods out there HHHEEEELLLPPPPP! Any advice more than welcome.
Please remember i am a noob so still getting my head round alot of the jargon, idiots terms would be appreciated. Thanks.
Jan 22, 2021
I did wonder if it could be a PSU issue. I don't have another PSU to test it with, are there any tests out there that can check if it is supplying the correct amount of power to all parts etc...?