E4300 restart error in Windows 10

Hi,

I recently bought a cheap E4300 on Ebay from a reputable seller. 

It came without OS but I installed Windows 7 Pro then upgraded to Windows 10. 

I also did all other necessary upgrades (upgraded the BIOS, upgraded as many drivers as I could find etc).....I do realise that Dell doesn't provide Windows 10 support for this laptop but for the most part everything has been working remarkably well. 

The only problem I've identified is that when the laptop needs to restart (either automatically, ie if doing updates or if I press "restart" myself) the laptop will go into a weird suspended state....The screen goes off however it doesn't seem to fully shut down - the light on the power button continues to blink and the laptop makes a clicking noise (which seems to come from the left hand side) as if it is trying to boot up but cant. At this point if you try to "long press" on the power button to shut it down it will not shut down. The only way I have been able to shut it down at this point is to remove the power cable and shut down on battery (or else unplug and re-plug in the cable) at which point it will reboot normally. 

Initially I thought this error might be something to do with either sleep or hibernation mode however if I choose to send the laptop to "sleep", then re-wake, it powers up normally. I also tried turning off hibernation completely  using command prompt (as admin) however this has had no effect. 

I have also tried playing around with different permutations in the power management options, again to no effect. 

Can anyone help or point me in the right direction?

Thanks!