Try to remove the rams if you have 2 rams on your PC try to remove one and if this problem continues follow this steps below
STEP1 - Try to put an old video card and tell me what happens if this not work follow this step 2
STEP2 - Verify your specs DDR, if your specs is not having the same DDR
you need to buy all specs of same DDR. and if this method is not working follow the step 3 is 100% working BECAUSE I tryied
STEP3 - Go your computer to an assambler.