Solving Freezing issues in Windows 7
I seem to have found a way to solve the freezing issues that many people are having in Windows 7. I have found the issue to be with the video drivers that most people are using. After doing a fresh reinstall of windows 7, I found that, when I used the windows video drivers, Kohan worked fine without a freeze for a long time, 15 - 20 games. Before using these drivers, I was getting freezes about every 4 or 5 games. It seems that, when using the Windows drivers, the game would, at times, "hiccup" but recover from it rather than completely freeze.
Please read through these fully before starting.
Before going through these steps, install the Driver Sweeper found here. This is a good tool to remove the video drivers.
Anyways, you can do a total reinstall of windows 7 if you like but that shouldn't be required. Here are some steps that should fix your setup so that Kohan runs well.
1) Uninstall your ATI / NVidia software. I believe the ATI one is called Catalyst. I don't recall the name of the NVidia one. Either way, just go to your Control Panel, Uninstall a Program, find your video driver software and uninstall it.
2) Uninstall your Video Drivers. This can be found under Control Panel, System, Device Manager (on the left side). When the Device Manager list comes up, look under Display Adapter, find yours (there should only be 1 listed) and open up the properties. Go to Driver and click on Uninstall. Make sure you check the "Delete the Driver Software for this Device" before clicking Ok.
3) Follow the instructions on the Guru3D link provided above to clean any remaining video driver files. You'll have to reboot in safe mode and run the Driver Sweeper to do this. Make sure you run Windows 7 in Safe Mode upon rebooting. Do not allow Windows 7 to reboot normally or it may reinstall the same drivers you just uninstalled.
4) After cleaning it out in safe mode, reboot your computer normally. Allow windows to manually find the drivers for you. Windows should find use the Microsoft Drivers which seem to work well with Kohan.
5) Verify you have the right drivers installed. Go back to your Device Manager (see #1 if you forgot) and check the Display Adapter. Again, go under the Driver Tab. You want the Driver Provider to be Microsoft Corp.
Alternatively, you may find the device drivers for ATI here. Just scroll down to the Microsoft Corporation WDDM listing. If you are using NVidia, just go to the NVidia listing. If you prefer, you can even just use these drivers on step #4 rather than having Windows find it for you. It may work better this way.
Example: ATI Radeon HD 4800
Device Provider: Microsoft Corp WDDM 1.1
Driver Date: 4/24/2009
Driver Version: 22.214.171.124.5
If confused, feel free to ask. I am currently testing other drivers and will try to find ones that work since the Microsoft ones would not work for some of my other games. If I find any recent ones, I'll post them up here.