OK.. Ill start with saying there are many questions and there is a lot to read..oh yeah and I don't know what I'm doing so if you think you have to patients to proceed, please do! Overclocking Stress test programs like OCCT always pass the test. I notice my overclocking instabilities during hours of game play. Recently I haven't been playing anything new and exciting so I left my overclock to 875MHz @ 1.075v. Ill get this out of the way first.. I have no idea what I'm doing when it come to overclocking. I just go by threads that I read but most are not helpful. I recently started playing Stalker COP, hours in to the game I got a black screen but could still here game play..as if my drivers failed or something. I know this game has many stability issues so I thought maybe it was the game. But after I alt ctrl del back to windows I noticed my overclock had reset back to stock speeds so I thought maybe I'll try something new.. (don't forget about the part where I said I don't know what I'm doing) So I thought to my self, give it some more voltage.. that's what people say to do when you have problems.. so I did I put it up to 1.088.. Then I had another thought.. I lowered the clock speed to 850 thinking id be double safe.. anyway.. thought all was running well but this time maybe 30-45 minutes in to the game it completely froze followed by a Blue screen. Now my questions are as follows.. Should I have just upped the voltage? or just backed off the clock? Is it possible I should be lowering the voltage because my specific card cant handle that high of a voltage or is 1.075 a safe spot? If lowering the voltage is the case I would like to start from scratch. So if that is the case if someone could somehow teach me or guide me how to overclock from the beginning.. as in what voltage and clock to begin with that would very very much appreciated! I've read in multiple threads to not go over 1.088v to stay away from the death zone of 1.1 and over. So I guess I would like to see how high I can go with up to that voltage but I guess what I'm trying to figure out is if maybe that voltage is too high for my card? because Ive try soo many clock speeds at that voltage (1.088) but depending on the game ill get problems. If voltage is not my problem, perhaps I should maybe just have different profiles for different games?.. Anyway for now I'm just concentrated on one game so if I can just get that one stable ill be good for now. Im running on air and temps are not a problem (Idle 35 and max 70 when I had it to firstname.lastname@example.org), Im using EVGA Precision for overclocking (2.1.2) and I did not bother to overclock the RAM on the card. I have the latest nvidia drivers (295.73) I know these are new drivers but I had the same problems with the older ones and beta drivers too. Let me know if you need more info. Thanks!
Most overclocking programs will not let you set the voltage beyond 1.15 or so and it is safe as long as your temperatures stay in check. How long did you run your stress tests for? I would run it for 30 minutes at full resolution to be sure of stability.
The fact that you got a BSOD but passed GPU stress testing sounds like a CPU issue though. If your GPU overclock at failed it should crash to your desktop at worst and re-initialize the driver. Have you overclocked the CPU at all?
The best way to regain stability is by lowering the frequency but raising the voltage is also effective and as you said doing both is doubly effective.
The card will lower the frequency and voltage if it is not being used so the reason it was at stock speed when you went back to windows may simply be because the game had stopped responding and therefore there was no load on your video card.
But note that your specific chip is unique and it may not be able to accomplish the clock speeds that are seen by other chips.
Like bardacuda said, it is weird that you got a BSOD despite passing GPU tests. Definitely double check your CPU overclock.
Another note: run benchmarking software after you determine a stable GPU overclock. Use the stable overclock that gives you the highest benchmark scores - a high clock doesn't guarantee better performance.