OCP stands for Over Current Protection.
Likely the card is failing. But it is possible the 3d drivers took a crap
Being it is over 10 years old, time to spend the same amount for a tank of fuel for a car, and get a much more modern card that is far more capable.
For now, you could press F8 during windows boot up, jump into safemode, and uninstall drivers to see if it stays working during normal bootup