Np, just a quick FYI, you may need to increase you fan speed by about 10%... try that when you see artifacts, if it doesn't clear it, then decrease the clock by 5. : )
Don't worry about frying your card ok, as long as you don't go mental with the sliders you will be fine. Happy overclocking.
Some people like to see there temps when overclocking just so it doesn't get to hot, not really needed but some cards are a bit picky when it comes to being overclocked and generally get hot much quicker.
So if you want, download Speed Fan and as you are overclocking keep an eye on the temp. General rule of the thumb is as long as its below 85c, your fine and dandy.