NB! This only covers WindowsXP, check the comments to see if someone had success with other Windows versions. The ppl behind Razer said they will make patches for windows2000 this year, with their Diamondback release.
Before you begin. It may have an affect on other usb devices, both positive and negative. So test with only the mouse connected first, then try adding the other devices and see if they work. If they don't try decreasing the samplerate, or go all the way back to the original file. But noone wants to do that, once they feel the power of 500hz
1. Locate usbport.sys in %SystemRoot%\System32\Drivers 2. Take a backup of the file, save it like usbport.BAK for instance. 3. Hexedit the file, locate this sequence of hex values: "3C 08 73 09 C6 86 0A 01", look in FAQ if you can't find it. (You can google for one, a lot of free hexeditors on the net. I used Hex Workshop 4.0) 4. It's found at different offsets depending on what usbport.sys version you got. non-SP/SP1/SP2 5. Replace that string with this one: "B0 04 73 09 52 8A 0A 01" 6. Save&reboot 7. Go into safemode (this is to avoid WFP), replace the patched usbport.sys in both %SystemRoot%\System32\Drivers AND %SystemRoot%\System32\dllcache (hidden folder) 8. Reboot, and it should all work fine. 9. Back in WinXP, check samplerate, and you SHOULD notice the change. For the ones with total blindness for such things; you will notice that sensitivity feels LOWER. Other things: Better responsetime/less jitter/mouselag/whine from you.
And this is the 250hz patch. 500hz : "B0 02 73 09 52 8C 0A 01" 1000hz : *Removed* 500hz should be enough for all at this point.
As you notice, the second hex value defines the milliseconds. 1000hz is the highest samplerate possible. Since the number is set with a whole number, and the lowest whole number is 1.
Mice and reported success: Intellimouse Explorer 3 - 250&500hz&1000hz Logitech MX300/310/500 - 250&500hz Logitech MX510 - 250&450hz Razer Viper - 250&500hz (doesn't fix the skipping) By RaZiel
AFAIK the 2 files are originally come from the guide of Aiming by RaZiel. Search for it with google, athough you have now problably more luck if you search for it with the terms aimingbyraz.zip Still the guide is old, recommended are only to use his hints, skip the hardware stuff.