Increase AMD Radeon HD 5700 Memory or recommended upgrade

[Twiztidpenguin]

I recently started playing AC: Unity but I am getting terrible FPS. I ran my system through systemrequirementslab.com and got back the following information.

Intel Core i7 CPU 930 @ 2.8 GHz
AMD Radeon HD 5700
Dedicated Memory: 1010.8MB
Total Memory: 4.0 GB
RAM 14 GB
Windows 10 64-bit
1.6 TB HDD

My question is how do I increase the memory used by the graphics card so I can utilize the full 4GB?
I have read on some pages that dedicated memory is as good as the card is going to get, if thats the case, what are some recommend upgrades? I was looking at the Sapphire Radeon NITRO R9 380 4GB, but I don't know if the computer can handle it. I think my power supply is around 1000 watts.

 

[TechCIDLC]

Your computer can handle any graphics card!

 

[utroz]

Your card only has 1GB of ram on it. The 4GB thing might be it borrowing system memory which is way to slow. Get a new gpu as yours is pretty slow for modern gaming. Your system can handle the 380 no problem. You might want to consider overclocking your cpu as well.