Speed issues with Inspiron 5759 Windows 10

Hi all,

I'm hoping someone can give me some direction on this particular issue as it's been causing some grief for a while now. The laptop Inspiron 5759 has just come out of warranty ufortunately and I should have logged a ticket but the issue went away for a while.

Basically what's happening is occassionally when the laptop turns on it is horrendously slow, it can last for hours or even in a couple of instances a few days. It will occassionally go back to it's normal speed but it's unusable for that time.

Looking at the task manager the HDD is stuck on 100% throughout all this though the rest of the resources don't go about 60%~ish. Initially I thought it was Windows updates so I've put the connection to metered to stop it downloading them. This helped for a while but then the issue persisted again. It feels to me that the hard drive is the bottleneck but there doesn't appear to be any reasonable explanation why a year old laptop of higher spec should be running slower than a computer over twice it's age with a lower specification. I've done some research that suggested updating the intel storage controller driver and the bios should help. I've done this as well which again helped for a while but the issue has come back again recently and I'm at a loss as to what else to try. Just to add, I have run antivirus and antimalware scans, and reinstalled the laptop just to make sure there wasn't anything else.

Thanks in advance!