Windows 7 glitch?

Hi all.
Decided to give windows 7 a go after sticking with xp for years.
Jury is still out but it seems ok so far.
One problem at the mo.
I get the beep to say all is well then a black screen with a flashing cursor in the top left.
After some messing I have discovered that it is when I have a usb pen or extenal hdd plugged into my usb hub.
Why is this and can anything be done?
Cheers.

 

sometimes a bios update for your mother board can cure it but it's quite a common problem on some older boards my last pc build used to do the same thing i never did get to cure it

 

Your BIOS is set to boot from USB drives before your hard drive. Open up your BIOS setup and change your boot order, if possible, or leave out USB drives when starting your PC.

 

Thanks for the replies.
I'll look see if there is a bios update.
Just Playin, i'll check the boot order but as I get the post beep and then it happens I doubt that is the problem.
Doesn't the beep mean the boot order has been checked and the OS been found?
As you say, I can leave the external HDD unplugged but that is a pain, I just want my drives to be available on start up, not messing about plugging stuff in.
Oh well, it will teach me not to upgrade in the future.

 

A single beep at post usually means that the BIOS detected no hardware problems at boot time.

 

Oh right.
Might just put up with it for now.
Thanks all.