why did you crash ? Any clues about that? Since you are up again after reinstal, but the mirror restore does not recover the system completely (without any changes), it looks like something is damaged, but with the amount of info you give it is a pure gamble to answer this type of problem…
what were you doing and under wich conditions ?
Lots of trouble with graphic cards and rebuilds nowadays it seems.
But you say nothing has changed, so a change in performance isn’t logical.
Did you try the cheap check on the graphics card issue:
Steveinchicago confirmed this card has worked for him:
In regard to GPU - I had some issues with spiking that I could not solve through settings, the issue manifested most apparently when I had the option “Select Tool Shows Extra Info” active, and mouse movement would cause spikes. It was most pronounced with the Project Window maximized. I checked with some other Cubase users - some had similar issues, some did not. So it does sound like this could be specific to a certain component.
My solution was to spend 25USD on the cheapest modern video card I could find, and this solved the problem, or really lessened it to such a degree that it doesn’t happen. I saw this on both Win 8.1 and 10.
I was using the on board video of my CPU, i7-3770k, and bought this http://amzn.com/B004I5UDO6. It’s a Nvidia Geforce card.
It’s a logical way to nail down the device that causes the malfunction:
One by one replace them (you can borrow mouses, audiocards, …).
Other option is roll back to the original copy, and change no drivers at all. That should be the exact same behaviour as in the past if you say nothing has been replaced. If not, something is damaged.
And you have tried starting Cubase in Safe Mode ?