If you use win7 (or Windows Server 2008 R2) and use a DX11 video card inwhich DirectX Diagnostics Tool reads DDI Version: 10.1 under the Display tab there is a fix from MS. What you do is click here: The DirectX Diagnostics Tool incorrectly reports DirectX 11 devices as DirectX 10.1 devices on a computer that is running Windows 7 or Windows Server 2008 R2 and click on "View and request hotfix downloads" link in the upper left side of the webpage. Follow the instructions also follow the instructions MS emails you. I am not sure if it will fix a DDI Version reading 10.0 for those using a DX11 video card using either Win7 or WS 2008 R2). This fixed the stuttering in Dirt 2's replays were there is dirt kicking up from your car. Also, all the stuttering I use to experience when I return from a race back to the outside of the trailer (using tessellated crowds) is also gone. Guide for those who can't get the DDI hotfix to workIf you are unable to get the DDI version to change this maybe an indication that your previous installed video card is still being recognized by your OS. Below is a guide to help you but it's a lengthy process. There are a few things you can do if you want to manually uninstall drivers: First section 1. Use the uninstall program from CCC or use the add/remove option to remove your drivers then reboot. 2. Once completed remove Ati Tray Tools, AMDGPUClock, Rivatuner, etc. Then reboot as needed. 3. Remove all ATI files from the windows\system32\ sub directory (Hover the cursor over the file to make sure it's a AMD/ATI file. Most start with atiXXX.XXX). These files are normally deleted once you install your monthly Cat Driver. You want to only manually delete them if you are experience a serious problem. 4. Goto: X:\Users\Administrator\AppData\Local\ and delete ATI sub folder (also look for sub folders for ATT, Rivatuner, etc and delete them) 5. Goto: X:\Users\Administrator\AppData\Roaming\ and delete the ATI sub folder. (also look for sub folders for ATT, Rivatuner, etc and delete them) 6. Type: Windows Update in Start's search box. Goto Change Settings. Look at the section that reads Import Updates. Change it so it reads "Check for updates but let me choose whether to download and install them". This will prevent your OS from brute forcing old driver installs once you've uninstall them upon bottom. 7. Click Start, goto devices & printers. Make sure there is no yellow triangle in the "your name"-PC. If there is right click on "your name"-PC and select troubleshoot. Follow the instructions The next few steps are a more involved methods of removing all driver and related traces. First, check to see what kind of backup driver is loaded for your video card after you've removed your current, monthly cat drivers. 4000/3000 series users may see a backup, old Cat driver without CCC capabilities once you've removed your monthly Cat Driver. This allows them to still use Areo and other effects, etc even though they don't have any current monthly Cat Driver installed. This is normal. If you check windows update you may find Cat driver for your 4000 series card. That's what that update is for. That backup driver shouldn't be used to replace your monthly Cat/driver. If you are not experiencing any more problems you should keep the backup, older driver and stop at this point and just install your current monthly Cat release drivers. Others may not have a backup driver when they uninstall their monthly Cat. This results in not having any Areo, etc effects on the desktop. This is also normal. I've not found any older Cat drivers for the 5870 once you uninstall your Cat drivers. If you are having problems and you've already uninstall your monthly Cat driver and rebooted your PC then goto Device Manager, Display Adapter, right click on ATI Radeon HD XXXX Series and uninstall it. Then reboot. Follow the steps below with caution: Second section 1. Type: CMD in start's search box 2. Right click on CMD from the list and Run as Administrator 3. At the dos prompt typed: set devmgr_show_nonpresent_devices=1 (this will show all hidden devices in Device Manager) 4. Type devmgmt.msc (this will take you to Device Manager). Click on View and select show hidden devices 5. Look in Display Adapter for any grayed out video cards and uninstall them (or any old video card devices). 6. Goto Monitors and uninstall all gray out monitors listed (or any old monitor devices). Finally go to Sound, Video and Game Controllers and uninstall all ATI High Definition Audio Devices 7. Open Regedit then backup your Registry by: (type: regedit in the start search box. Make sure that Computer is highlighted. Go to: File then select Export. Select a name and location on your hard drive and save it.) Next do a "Key" search for ATI Technologies. Click on Edit then Find and enter ATI Technologies. Only check the option to search for Keys. If you find those keys delete them and their sub-keys (icons that look like yellow folders). (this will also remove your backup Cat driver if they are still present in the registry. 8. Turn off Pagefile then Reboot your PC. You do this by: (Right Click on My Computer. Click on Advance system settings. Click on Advance Tab. Click on Performance Settings button. Click on the Advance Tab. Click on Virtual Memory Change button. UnCheck Automatically manage Paging file size for all drives. Select no page file for the hard drive using pagefile. Hit the Set button. Hit Ok Button. Hit Apply Button. Hit Apply Button again (if required). Popup screen will tell you to reboot the PC. Do that at this time). 9. Once at desktop re-enable your pagefile. Just undo what you did in step 8 10. Install your monthly Cat Driver. Then Reboot 11. Install the most current Directx. Type dxdiag in Start's search box to verify. Click on the Save All Information button. Afterwards exit dxdiag. 12. Install the DDI hotfix (KB975243) if your DDI reads 10.1 when using a Win7 with a DX11 video card. 13. Rebuild your Index: (type: Index in Start's Search box. Hit the Advance Button. Hit the Rebuild Button. Wait about 5 minutes for win7 to rebuild the index) You only need to do this ONCE. If all goes well and the problem is fixed all you need to do from now on is to use ATI Catalyst Install Manager found in Uninstall Programs (Win7) or Add or Remove Programs (XP). Reboot and install the current month's drivers from then on out. Edit: Please make sure you use IE 64 bit if you are using a 64bit Operating System. Apparently, per 20mmrain, MS will not provide you the correct files if you don't use IE 64 bit. Disclaimer: These instructions were left for those who are experienced with editing, tweaking and making changes to thier OS. You perform these instructions at your own risk.