Buying a graphics card as a gift

Hi community

I would like to buy my Dad a new graphics card for Christmas but i don't know much about low profile graphics cards.

This is round about everything i know about his Desktop pc:
-Intel i3 (3.0Ghz or more don't know if its dual/quad core or not)
-8Gb RAM
-Motherboard is a micro ATX motherboard i think and its is the kind that is made specifically for his case (Computer was bought from PC World)
-He installed a Radeon 7750 low profile graphics card in a long while ago (don't know the on-board memory)
-Don't know the PSU's watt amount sorry
-The case is a micro ATX as i can tell as its much smaller than my computers mid tower case
-His run Windows 10

Could anyone tell me if there is a better low profile card out there as i can see my Dads computer is struggling playing Dishonored, Skyrim and Fallout 3(He plays on ultra even when i told him his card can't handle ultra).

Thanks