Solved Random freezing

My sons PC has recently started to freeze randomly, during playing games. The whole system just freezes, and only a reset can fetch it back.
Its a self built system, that's been running OK for ages.
Specs..
AMD FX6300 CPU, AMD RX570 GPU, 16Gb RAM, Gigabyte GA970a ds3-p MOBO. 1Tb WD HDD 500W PSU. Windows 10 V2004
the system did have an AMD Athlon X3 CPU until christmas when it was changed out for the FX6300.

tried all kinds of things to cure this, updating graphics drivers to most recent versions etc. all to no avail. Games tend to freeze after around 10mins of gameplay
The games he is playing are on the Roblox platform, but not all games freeze up. There is no warning about this. Occ does this with Minecraft as well.

I did think it was an overheating issue, and as the case was rather small, I upgraded the case, and also bought a coolermaster evo cooler for the CPU, as it was tending to run a little hot at around 65 to 70degrees. Now tops out at 35-40degrees under load. GPU sits at around 65 degrees.

Oddly enough tonight, I got him to play a game he had installed on the system, and he had no issues. The game was cranked up to its max resolution of 1080P.
He can also watch 1080p videos full screen on you tube with no issues.

I am more than a little stumped as to the cause of this, and I am fast running out of ideas. I am more suspecting software rather than hardware, but if anyone has any ideas I would be grateful.

I thought I would run some stress tests on the components. CPU seemed OK. Ran FurMark for the GPU and also no freezes during either benchmarking or Stress testing at 100% of GPU power. Ran an HDD test and oddly enough got a Caution on the SMART test using CrystalDisk Info, and HDD tester. Am I looking at an impending HDD failure??. Also I have just been told that when he is playing games that dont crash, he gets random 3 beeps through his headphones (wired). Are these MOBO beeps. The system appears to POST correctly, and as far as I am aware the UEFI is up to date. Could this be a memory issue??

Just to update, I have attached a screenshot of the Crystal disk info.
PSU is an Aerocool integrator 500W 80Plus

Thanks for the reply. It has started doing some odd things, likel chrome not opeing up, but being active in task manager etc.
Its still off that its only certain games it freezes on and others fine, and also games installed on the HDD are fine, but certain games needing an internet connection freeze. Could a failing HDD do this??
I have a spare laptop 1Tb HDD that I can use as a temp measure, but I assume these days SSDs are better value..
Will swapout HDDs and reinstall windows from scratch this weekend and see what happens. Will do a memory test as well, as the 3 beeps seem odd, but its been reported by a teenager

Thanks for the replies, appreciate your time.
There are 4 4gb sticks of ram.
I ran a chkdsk yesterday, but from within windows. Didn't find anything, but will run again tonight with the /R switch.
Other people suggested reinstalling windows, which is pointless on a failing drive. I will order up an ssd depending upon chkdsk, and reinstall on the hdd I have spare in the interim . Yes just said there's no sound now on the system. Something clearly amiss........ I'll look at the PSU link.

Well amd site recommended min 450w for an rx570. I've got a 500w Bronze rated one. Suspect a new one needed as well....

Took the system 6hrs last night to run chkdsk /r..... It then did another hour shutting down saying configuring Windows... Ran out of time to post logs... Will do when I get home from work.

Attached is the txt file created.

Thanks.... Backing up the data now. I've checked the 2.5in hdd in a caddy with my laptop and checks out fine with Crystal hdd check. He's tried a game installed on hdd, call of duty, and this freezes.., but halo didn't.... Only 1 game he plays on Roblox dosnt freeze, no idea why.... Anyhow, will replace drives tomorrow, just creating install media for 10pro 21H1. Will keep you updated....

Installed new drive and a fresh copy of 21H1. I've only installed the necessary drivers, and left it using windows defender, rather than my usual av software. Running edge rather than chrome. All seems ok at the min, but virtually nothing is installed on it but the necessary stuff. No freezing in his games so far so fingers crossed. Will install the other stuff he uses 1 by 1 and see how things go.
Thanks for all the help and advice so far

Ok......the system froze again for him, but when he restarted, the system said the bios was corrupted. It reloaded the bios from a backup, and it was fine, but now thus new issue has confused me. Is this a potential motherboard issue all along being marked by a failing hdd. The bios is up to date, would it be wise to reflash the bios with the same version....

Just a thought...as I noted before we switched case, the CPU was running hit and at times but to 75 ish degrees. Could this have damaged the CPU, causing these issues...