Okay this issue has been really pissing me off lately. Heres the deal. I play a first person shooter called Quake 3. Ever since I've been using this mouse I've had a hunch that for some reason my LG (Lightning Gun) was unfairly disadvantaged compared to other players. I used to think it was because I had semi-crappy fps. But I recently discovered that Logitech setpoint was the culprit because when I don't have it installed and use the XP plug and play default mouse driver, I can shoot way better, especially lightning gun. The difference is like night and day.
The problem with not using a driver is that this mouse (Logitech mx518) has two on the fly sensitivity buttons above and below the mouse wheel. I use the mouse 3 (mwheel click) to switch to a weapon. So I am constantly accidentally hitting these on the fly buttons which change the mouse DPI to different settings, which changes the speed of the mouse and totally screws me up. And also the mouse movement just feels weird w/o the logitech driver and it's also the only way I can disable those buttons.
Mouse - Logitech MX518
Computer - Pentium 4 2GHZ, 256 DDR ram, Windows XP Home Edition
Driver - Originally the one off the disc it came with but I tried the newest one on Logitech's website a couple days ago hoping it would help but it did the same thing.
Observation: My only thought on the cause for the lag is that with the Logitech setpoint program, my mouse clicks are having to run through the Setpoint program, in which case they would be at the mercy of my systems performance. Seeing as I don't have a whole lot of ram and my hard drive is only an ATA-100 speed, that performance isn't that great. I have tried different USB ports but that doesn't help.
I always use the Windows driver... I never bother installing the Logitech software. I use the MX700... so I'm not sure how it differs from the 518... but my buttons are just another set of scroll buttons.
Errr... uninstall the software and make sure you don't hit the buttons?
Sorry, but I'm at a loss. The ONLY thing I can suggest to you is to not install the Logitech software and see if the default Windows driver will allow you to reconfigure the buttons. It SHOULD allow you to, as I am reasonably sure I can change them with mine. Of course, I haven't had the need to check, so I'm not absolutely sure... I'll have to check it out and get back to you.
Yours are scroll buttons, not on the fly DPI buttons like mine. Those buttons are a mechanic of the actual mouse hardware and have no connection or configurational options from windows. Only setpoint can change or disable them. And trying not to hit the buttons just doesn't work. They are far too close to the mouse wheel and I click that for my rocket launcher all the time. I just can't avoid not hitting them every time, especially during a twitch-reaction highspeed brutal fight in ra3.