My old graphics card (an NVIDIA GeForce 8500 GT) packed in a few months ago (showed multicoloured stripes on the bios screen and X refused to start) and I have since disposed of it. I am currently using a spare NVIDIA Quadro, which lspci calls this:

It technically works, but Steam refuses to run any games and one of the monitors' refresh rates cannot be set to something that doesn't look blurry without reducing the resolution to something that is either very small or doesn't match the monitor's aspect ratio.

I have tried multiple cards which claim to work for games, including the NVIDIA GeForce GT 630, AMD Radeon R7 240 and multiple others and when trying to boot with any of them, Fedora will load as normal, but as soon as X starts, the computer slows to a near halt, moving the mouse pointer at 1 fps and barely being able to run Firefox. I can't even run the terminal or CTRL+ALT+F2 to run lspci as it still performs very sluggishly.

The same effect is observed when trying boot discs of Fedora 20 Xfce edition and Debian 7 and affects every version of the kernel it is attempted with.

Does anyone know how I could remedy this issue (i.e. have a card that both allows X to load, and allows video games to function).

Best regards, and thanks for any help,
UltrasonicMadness

Have you tried installing the NVIDIA proprietary drivers? My GT 640 runs fine with the NVIDIA proprietary drivers from the Debian repository as did my old 9800 GTX (based upon the 8800).

I have tried installing drivers but the computer runs so slowly that it cannot be done. My last card and the Quadro do not need drivers.

That your computer runs so slowly indicates that the system falls back to software rendering, putting severe load on your CPU.
I recommend to start the system without a GUI running and install the appropriate driver from the commandline.

As TobiSGD says, then you should install them from the command line. You can press Ctrl+Alt+F1 then log in as root and stop your display manager with something like "service gdm3 stop" or "service kdm stop" and follow the instructions here:
https://wiki.debian.org/NvidiaGraphicsDrivers

How would I go about starting it without a GUI?

(without loading X at all)

When starting your system and the bootloader appears (on Fedora I would guess it is Grub 2) add this to the kernel commandline:

I have tried entering your command into GRUB, both by entering the command into the command line (pressing c) and then starting the latest kernel (3.14.9-200.fc20.i686).

I also tried entering edit mode (pressing e) and adding your command as the first line (attempted with both rescue mode and the latest kernel) and the message "Booting a command list" comes up along with the graphical boot screen followed by the graphical login screen.

You have to add the command to the end of the kernel commandline, the one that starts with the linux command. For example, on a Debian system it looks like this:This will of course look a bit different on a Fedora system, but you should be able to determine to which line you have to add the command.

My most humble apologies for having taken this long to have tried and tested this. I have been quite busy recently.

Anyway, I followed the instructions here in order to install the driver, in conjunction with disabling the GUI while doing so.

The install process seemed to go well, as the installer showed no errors. I rebooted the computer into the GUI and found that the problem is still very much there, with delayed mouse movement and quite a delay between pressing a key and the OS recognising this input. I was able to log in and see that AMD Catalyst had installed (in the Settings submenu).

As it turned out I am using kernel version 3.15, and I don't have any spare 3.14 or earlier kernels to boot with. What would you recommend doing at this point (like a way to use yum to get an old kernel, or an open source driver (akin to nouveau))?

Best regards
UltrasonicMadness

Update: Got another GeForce 8500 GT from Ebay and it works fine. Thank you for the help!