No BSOD but computer restarts without warning on a regular basis

Hi everyone
I'm not sure if this is the correct forum out of all the ones on offer, but as it's about my computer regularly crashing, I thought I'd post this here. If it's incorrect, I apologise...please point me in the direction of a more appropriate forum.

Ever since I bought this computer a year ago, my computer randomly crashes. It's often about 20 - 30 minutes after starting up, but not always. Sometimes it can be after several hours' use. There's no warning; nothing comes up to tell me the computer will restart, it just does. I wondered if it was linked to updates and I've set the system to allow me to install the updates manually, but that hasn't fixed it. I also disabled the forced update in Task Scheduler and that seemed to work for a while, but now it's happening again with monotonous regularity.

I've done Google searches on this and I can't find anything other than this page https://justpaste.it/HowDisableWindows10Update. I appear to be the only person experiencing this.

If someone can help please, I'd be so grateful. I'm being driven mad by this.
Thanks in advance

Mark

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