I have a problem with my PC, since i bought a new graphics card (NVIDIA geForce GT 730 2GB version) The driver (graphic) started crashing, when i play like new games such as (NFS Rivals ) and even when i am on Firefox sometimes i get like wierd colors on the screen and i have to shut firefox down so it can stabilize my PC is kinda old but, i didn`t have any problems with my PC with my old graphics card (512 MB) this is happening with the New One. BTW I have the requrements for the Graphics card such as the power supply wattage ..
CPU: AMD Athlon 64 x2 5200 + 2.7 GHz (overclocked to 3.0GHz)
RAM : 3 GB
Windows 7 Ultimate 64 Bit
Honestly I'd just upgrade your entire rig. There are a few sites out there that you can use to build your computer and price everything out and find the best pricing from multiple retailers. Just search around for em!