/dev/fb0: No such file or directory
 

I'm attempting to use fbgrab and fbcat, but it requires /dev/fb0 to exist. I've checked in /dev/ and it unfortunately doesn't exist

How can I create this file? My computer specs are in my signature and I'm using the proprietary ATI Radeon 4500 graphics driver

Did you look at the Frambuffer HowTo page that is linked from the fbgrab home page?
http://hem.bredband.net/gmogmo/fbgrab/

http://www.tldp.org/HOWTO/Framebuffer-HOWTO/

I've tried reading up on the part specific to ATI cards but I don't trust instructions that are untested.

You will want to use the vesa framebuffer if you are going to stick with the proprietary drivers. Assuming your kernel has support for it, you'll need to pass vga=somemode to the kernel. Check the "What VESA modes are available to me?" part of the document you were looking at.

Adam

1. first check that framebuffer is enabled in your kernel
Execute this command
It should return something like
2. If the answer is yes you should have in your boot options
(your grub menu or lilo menu) something like
or vga=792, etc. according to your screen size and resolution
(If you have a 15-inch, 791 should be fine)

If framebuffer is not enabled in your kernel you'll have to
rebuild the kernel by enabling these options first