First i would say locate a file called DiskCacheArena and delete it to see if that solves it,
You can remove/delete the DiskCacheArena file by going to the following location:
32bit: C:\Program Files\Electronic Arts\BioWare\Star Wars - The Old Republic\swtor
64bit: C:\Program Files (x86)\Electronic Arts\BioWare\Star Wars - The Old Republic\swtor
Doing so will not harm your installation of the game as it will be re-created upon launching the game.
Try turning off vsynch if it is enabled.
Failing that try uninstalling your video card drivers and re-installing them.
Run a chkdsk c: /f and a sfc /scannow
lastly try a program like this to test system stability http://download.cnet.com/Heavyload/3...86_4-9736.html