cgminer slowed down after fresh windows install

[Martok88]

I did a fresh install of windows to solve some stability issues on my mining rig. Afterwards my hashrate is about 15% lower than it should be, across all 4 GPUs. I'm using exactly the same cgminer settings as before, as well as the same video drivers. I tried using a few versions of cgminer and GPU drivers, with the same result.

Basically I'm wondering what factors might cause this other than the ones I've ruled out:

• graphics driver version
• cgminer version
• monitor being plugged in to different GPU, or not plugged in
• windows power settings

Here's the hardware I'm using:
PSU- http://www.newegg.com/Product/Product.aspx?Item=N82E16817703037
CPU- http://www.newegg.com/Product/Product.aspx?Item=N82E16819103888
GPU- 4x http://www.amazon.com/gp/product/B009B6Y01Y
RAM- http://www.newegg.com/Product/Product.aspx?Item=N82E16820231314
SSD- http://www.newegg.com/Product/Product.aspx?Item=N82E16820171667
Mobo- http://www.newegg.com/Product/Product.aspx?Item=N82E16813157280

[os2sam]

You were probably using older .bin files before which were compiled on a different Catalyst/SDK combination that was more efficient.  So you can either try to backlevel those to the earlier configuration or just keep what you have since it is working.

[Martok88]

You were probably using older .bin files before which were compiled on a different Catalyst/SDK combination that was more efficient.  So you can either try to backlevel those to the earlier configuration or just keep what you have since it is working.

Thanks for the advice. How would I go about doing that?

[os2sam]

You were probably using older .bin files before which were compiled on a different Catalyst/SDK combination that was more efficient.  So you can either try to backlevel those to the earlier configuration or just keep what you have since it is working.

Thanks for the advice. How would I go about doing that?

By installing older Catalyst/SDK combinations that you had used previously, delete the .bin files in your CGMiner directory and run CGMiner to create the new .bin files for your new configuration and try it for a while, then repeat.

It's allot of trial and error.  Which is why I also said your other option was to keep what you have.
Good Luck,
Sam