Is the video card overclocked?  (I am assuming yes since it is water cooled and everything)  If it is, remove the overclock and see if the problem persists.
 
Otherwise, it sounds like it could be a Windows driver update issue.  That would explain the screen going black (while swapping the driver to a generic Windows driver or an otherwise bad driver), and the appearance that the driver is being uninstalled without your wishes. Make sure you have Windows update driver downloading disabled.
 

 
If automatic driver downloads are enabled in Windows update, all kinds of weird issues can occur.
 
 

Sounds like you need to put the stock cooler back on to see if that fixes the black screen issue.

Cool GTX
Water Cooled GPU & 61C does not compute ... something is terribly wrong if your getting that hot

No, it is actually not.
At my system I can run water at ~38C while my gpu will be at ~46C at full fans (1600 rpm), on aggressive fan profile (1200 rpm) I am getting ~ 42C water and ~50C gpu and on silent fan profile (~900rpm) I am getting ~52C water and 60C gpu.
 
So it is nothing wrong to have watercooled gpu going up to 60C. Depends on radiator setup and fan rpm.

You mean additional 15-30mhz? :) Thats not so much, while silent pc is a huge win for someone who doesnt like headphones like me.
 
My card is running at 2100mhz with aggressive fan profile, and I can get higher only if I cool it down to 40C (~15C room temp, 2130) or 44C (~20C room, 2115) - and that is way uncomfortable with both room temperature and noise level.
I believe next frequency drop is 52C, next somewhere between 55-60C and next is even higher, so I am getting ~2070mhz on silent profile loosing only ~2% of performance, but letting my pc runs very quiet so I can down volume level of my speakers which is great for night gaming.
Even if my frequency will drop down to 2040 or even to 2010 - that still only 3-4% of overal performance loss. 
 
And card is made to run up to 89C, while pump can run up to 65C water temp, so why not? The only concern of that silent profile of mine is that my HDDs is warming up to 47C and my ram is going up to 60C, I don't like it, but at the same time HDD can stay temperatures up to 50C with no harm and RAM specs shows 85C max temp. CPU is not troubled at all especially under gaming load.