I haven't checked for you but is your graphics card certified approved by SolidWorks?
Whilst a lot of problems can be caused by graphics cards, don't be too hasty in thinking that it could only be that.
Has your PC done any automatic updates lately?
Have you run RX ?
Do you have other apps running in the background?
When was the last time you did a 'restart' and not just a shutdown and startup?
What other programs are running in the back ground? Have you checked you boot up and what programs get started when you turn on the computer? That sometimes causes the long start to the machine, and take up memory that is not really needed by those programs that could be used for SolidWorks.