8800 GTS and RivaTuner

Is anybody using RivaTuner to overclock the 8800 GTS?

I installed it since I lost fan control with nTune. Seems to work pretty nice. I followed a few tutorials to set it up, but I'm a bit confused on a few points.

1) In order for the hardware monitoring to adjust fan speed, I need RivaTuner running in the background, right? Is there any performance hit to this?

2) I setup a 2D/3D profile like in some guides I found:
http://forums.guru3d.com/showpost.php?p=2101795&postcount=34
http://home.comcast.net/~msl2/RivaTuner -clock speeds.htm
It seems to work great, except my memory clock is always overclocked (the fan speed and GPU do just fine.)

3) RivaTuner identifies my driver as 58.19 when I in fact have 158.19. Is this going to cause a problem?

Thanks for any help

I just set my fan to permanent 78% which did not make it any louder when inside my case and it dropped temps. That way there's no need to keep it running for dynamic fan control and it just loads oc settings at startup. And yea my memory always seems to be oc'd as well

So did you just have it set overclocking speeds at startup? I was a little confused by the 2D/3D speeds...I get that the 2D is when it's not in 3D and the 3D should kick in when it's running a 3D game, but it seemed to me that I had set two overclocking speeds to start up at windows. Maybe the GUI is just a little confusing on that point. If I click 2D, set my clock/mem to something low, then test and save for startup, then click 3D set my clock/mem to overclocking then test and save for startup, does this do what I want? ie, will it overclock it only when needed?

Under driver-level overclocking: I tested and set the 3D performance speeds and left 2D alone, I believe 'low power 3D' is the same speeds as 2D. What you said is exactly right. To verify it's working correctly click the magnifying-glass-over-IC icon in the 'target adaptor' customization and you can watch the speeds change in the graph.

For the fan I used 'low-level system settings' under the 'target adaptor' drop-down and set it to always run at 78% and enable that at Windows startup.