So I have the Radeon HD7850 and the computer is working fine, however when I check my GPU on 'run>dxdiag' it doesn't say Radeon HD7850, but Intel HD graphics family. Has my gpu not installed properly or does it just say this anyway?
1) Is your monitor hooked up to your new GPU, or still to the motherboard connectors ?
2) Maybe you have not installed the drivers properly for the 7850 ?
3) You might need to disable the onboard graphics from the bios for the GPU to show properly
It sounds like your motherboard's integrated graphics are still enabled. Is your monitor currently plugged into the GPU or the motherboard?
NOTE: Consult your motherboard's documentation when altering BIOS/UEFI settings! To disable the integrated graphics you must go into your BIOS/UEFI Setup when your machine first turns on. Look for a menu called "integrated peripherals" or something similar and disable the integrated graphics. Then reboot and plug your monitor(s) into the GPU. If the drivers are already installed, check dxdiag again and see if your 7850 is now listed.