could be a number of reasons (start with 1)
X= means C:\ just in case you have changed to something else.
1. X:/username/app data/minecraft then delete the bin folder after done that go to the minecraft website and play in browser
and it should redownload the bin folder and that should fix it hopefully.
2. your graphics driver may be corrupt,unstable or incompatible with the card install a previous version that you know that has worked
before to test.
3 java - try fully removing your java and reinstalling it see if there was a problem installing or configuring.
if your not sure how to remove java or the old versions you can use this software and unistall safely
hope it helps.