Pratyush_1 :
Will there be a performance decrease?
Also I wanna know does my motherboard officially aupprts ddr5 graphics card. I searched in Google but I didn't got a relevant answer
Graphic card memory doesn't "need" to be compatible with your mobo, the interaction is within the card, specifically between the GPU and card memory.
Which GPU are you planning to get?
Edit: I just read you want a 750, search for the "TI" version as it is more powefull, it will fit and work well in your mobo so don't worry. What are the other components of your computer?