This utility allows you make a lot of modifications to the registry settings of your Geforce videocard. All registry mods work. From version 2.0 on the GTU includes a working overclocking feature (all earlier versions didn't do that correctly).
There are some beta options that you can use, but I don't know if (and how) they work. Try them at your own risk.
NVidia reference drivers: version 5.08 and later
ASUS drivers: the 5.16 or later drivers will work
ELSA drivers: the latest drivers are based on the 5.xx NVidia drivers, so they will work.
Some of the new options will only have an effect when you use the Detonator3 drivers.
Warning: GeForce Tweak Utility allows much higher speeds then possible for your hardware to run at. If you set the speed too high then you run the risk of overheating your card and damaging it. Please only use this feature if you know what you are doing.
This release should fix some problems under W2k.
On some systems it could happen that some games/apps stopped working after starting the GTU. This problem should be fixed now.