Hope these can save someone time. Solutions found around the internet, some of them are not credited to me.
Updated on 24 Aug 2017, getting useful information from here.
The new recommend way is to use latest release of new ethminer.exe, latest drivers for better performance. Always use CUDA to prevent hogging one of your CPU core to 100%.
Q: My miner crashes on latest drivers / all cuda drivers are busy
A: Go to NVIDIA Control Panel -> Manage 3D Settings -> DSR - Factors -> 1.2X.
Q: I only get 3MH/s
A: Install latest drivers and go to NVIDIA Control Panel -> Manage 3D Settings -> Optimize for compute performance -> On.
Q: Overclocking has no effect on hashrate.
A: AFAIK, Some miner doesn't care your current clock speed, you have to flash modified bios into that card, use Maxwell II BIOS Tweaker and NVFlash to do it. Overclock memory speed, not clock speed. You need clock speed for GTX970
Q: Why I get like 17MH/s while others can get like 23MH/s
A: This is because NVIDIA did not treat your miner as performance intensive app. You need to force it. Run cmd as admin,
cd C:\Program Files\NVIDIA Corporation\NVSMI
nvidia-smi -ac 3505,1455
3505 is your memory clock. If you modded your bios you need to change this to your value.
Q: My screen so lags while mining
use "--cuda-grid-size 1024"
Q: My screen tend to freeze until everything stopped working, had to hard reset
A: This bothers me a lot, the current solution I found is to quit the miner, wait the screen to flash for a second then continue to do other things.