win8.1 desktop freezes sometimes when going to sleep

[unwashed potato!]

is there any way i can see what is causing my pc to feeze when going to sleep? sometimes it's fine and will go to sleep, sometimes it'll all go blank but never fully sleep (the screens are turned off but the box fans are still spinning), and then it can't be woken up without having to hold the power button for 5 seconds and restart, but it does restart as though it was only asleep.

any suggestions for what i can do to find out what's causing this>?

 

[Semple]

The answer is No!

Sorry couldn't resist

It might be worth making a note of the programs that have been running each time this happens, see if you can rule out if its anything but the O/S that's causing these issues.

Edit: I've not actually checked the Event Viewer on W8, but have a skim through that about the time the computer goes to sleep to see if there's anything unusual that stands out.

 

[unwashed potato!]

thanks for the suggestion. i checked the event viewer and this error came up often.

Win 8 x64 event viewer error - (MTRRs) across a sleep state transition (S4)

i've checked and it appears this can cause my problem
http://www.sysnative.com/forums/win...mtrrs-across-a-sleep-state-transition-s4.html

and the suggestion is to check bios for an update. how would i do this? if not updating the bios any other thoughts what i could to do solve the error>?