Black screen on startup, can't enter BIOS or any other startup menus... Any advice?

[tempcheck]

Hi there, posted this on toms hardware but think it may be better suited here (apologies if not the done thing!)...

Toshiba laptop s50-b-15q
Intel i7-5500
16gb RAM
AMD r7 m260 Graphics card

Have had significant boot-up problems since the recent W10 creators (fall) update, with an average boot time of 1.5-2 hours for last couple of weeks (no issue from sleep and computer runs normally once up). In that time I see only a black screen (no cursor, looks to be off) but after a while normal login screen appeared. Cleared startup programs/services/fast startup, updated drivers (I can't access BIOs but look up to date), tried repairing the Windows update (failed), but problem persists.

Thinking it may be a GPU issue or possibly failed SSD drive (also an HDD with 800gb free space), but decided to use try rolling back to previous version of Windows in recovery options (as no boot issues before the update)... Machine was doing something, but on black screen for over 48 hours!

Looks like it was probably in an 'infinite loop' (difficult to know as I couldn't see anything - tried connecting to external monitor but no output), so finally powered off. Tried rebooting using all F-key combinations, 0 and esc, but still does nothing. Any ideas on other ways to access BIOS/bootup menus (with just a black screen)?

Thanks

 

[rgd1101]

MERGED QUESTION
Question from tempcheck : "Endless black screen after rolling back to previous version of Windows 10"

Hi there,

Toshiba laptop s50-b-15q
Intel i7-5500
16gb RAM
AMD r7 m260 Graphics card

Having significant boot-up problems since the recent W10 creators (fall) update, with an average boot time of 1.5-2 hours for last couple of weeks (no issue from sleep and computer runs normally once up). In that time I see only a black screen (no cursor, looks to be off) but after a while normal login screen appears. Cleared startup programs/services/fast startup, updated drivers (I can't access BIOs but look to be last available), tried repairing the Windows update (failed), but problem persists.

Thinking it may be a GPU issue or possibly failed SSD drive (also an HDD with 800gb free space), but decided to use try rolling back to previous version of Windows in recovery options (as no boot issues before the update)... Computer has now been on black screen for over 18 hours!

Question is what is best course of action now? Should I just force shutdown even though it may be doing something (and if so, how?), or is it likely in an 'infinite loop'? Difficult to know as cannot see anything.

I have all data I need backed up and have made a recovery install on usb, so what is best option afterwards... Repair, restore, reset or just reinstall Windows? Also how can I access these options with just a black screen?

Thanks