access bios Acer Aspire 7741

[RRH100]

I am trying to access the bios on my Acer Aspire 7741 Laptop so I can boot the computer from a usb card (I want to install Windows 10 - it runs Windows 8.1 Pro at the moment)
I have tried all the usual keys when starting up F2, F12, Delete, Enter, jujst about every key. I do get a brief look at what I think (!) is a bios screen as it is white writing on a black background, but it does not stop long enough for me to see it clearly.
Your help would be much appreciated RRH.

 

[w00sey]

The user guide on Acer's site for that model says it should be F2. You may want to check and make sure the laptop is being properly shut down and not just hibernating. While I don't know if this is the case for Acer laptops, I have seen some other brands that will show the same splash screen when booting up and when resuming from hibernation but the latter will not allow you to get into any boot options.