|"working perfectly until a week ago"|
What event happened a week ago after which you had these problems ?
Was there a power failure event ?
Was it after you installed some software or after Windows Update or some other program automatically installed some software ?
If you have installed Windows from scratch since the last time the drives worked properly, you must install the main chipset drivers for the mboard after Setup has finished, otherwise burner drives may not be detected properly.
Any device changes ?
"now cant access the bios setup"
With what ?
If this is a desktop computer,
- you should be able to access it with a PS/2 connected keyboard
- if you're using a USB keyboard, legacy USB or similar must be enabled in the bios in order for you to be able to get into the bios with a USB connected keyboard.That may or may not be enabled by default.
-if you're using a gender adapter on the end of the keyboard's cord to connect it to a different type of port
- the keyboard must be a "combo" model that is wired up to and designed to be used with both types of ports
- the adapter must be one for a keyboard - the one for a mouse probably won't work - the one for a keyboard is usually purple.
"using both convertx and nero(strangely burnt an iso image with nero ok earlier)and both dont burn/recognise any kind of disc."
You should NOT install more than one third party burning program at a time, because they often have at least one resident module that runs all the time (Nero software does) , and those modules are well known to conflict with each other and cause weird problems.
"yet when clicking on one it only recognises cd rom device"
When there is NO disk in the drive, Windows can assign various labels for the empty drive depending on where you look in Windows
When there IS a disk in the drive, the label beside the drive letter WILL CHANGE TO SUIT THE DISK.
If the disk has data on it, and it the disk has a volume label, the text beside the drive letter will be the same as the volume label.
If you insert a blank CD-R or DVD-R disk in the drive, in My Computer the label beside the drive letter will change to CD Drive, and on the icon for the drive there will be a tiny black bar on the disk image that has CD-R or DVD-R in white letters on it.