only error is kernel critical error about system lost power (that is because i hard restarted PC)

This type of crash can pretty much be narrowed down to hardware, driver & kernel issues – normally in that order. I fully understand you say you only have issues with destiny but quite simply the game cannot cause your system to crash - it is only bringing an underlying problem to the surface. The fact this hasn’t yet occurred in other games whilst sounds logical, is largely irrelevant as they each perform differing calls and put varying load on different components – I normally find MMO style games seem to put more overall pressure on the system causing these failures. Going to need some more information here: Have you had the 2600k since new? Assuming dxdiag is correct, this is overclocked to 4.4Ghz, I would expect some degradation at this point with its age, requiring more voltage as occurred on mine when I had one. When running stress tests such as linpack you really need 8+ hours, so many people I speak to think 30mins-1 hour is enough. What is the model of your PSU & how old is it? How old is the windows installation? It could be worth upgrading to 17763 although I prefer to format and avoid upgrades where possible. I had a rare issue recently where the page file got corrupted I believe during a power loss, causing sporadic crashes - could be worth deleting and letting windows re-create to eliminate.

CPU is on 4,4GHz for 3 days now and stable.. issue is here much longer. CPU is under watercooling at max 65C. PSU is 2 years old - Corsair 1000W. Win was installed in summer.

Sorry but i'm skeptical on what you are calling stable without knowing how this is being tested, something in your system is not stable. I'm guessing the Corsair is the CWT platform so it [i]should[/i] be good but can't tell without the model number, although even the best supplies can go faulty unfortuantely. Do you have any TDRs under warnings in the event log or any other warnings of note? I would probably start with imaging your current installation, then installing fresh just to eliminate an OS level issue but if this fails, it needs to replicated outside of d2.