Will need to know a couple of things before hand first. Such as:
1. PC Specs (CPU, PSU, Motherboard Chipset, GPU & RAM)
2. Purpose of video card (eg. games, video editing)
3. Screen resolution
5. Casing size (a slim chassis will need a low-profile card)
With those, it'll help shed more light on what to recommend.
P.S. Please read this before posting questions next time.