Increase USB polling rate?

Could you explain that again? I'm not sure if your gamepad is a USB device plugged into a converter that lets you plug 2 USB gamepads into one PS2 connector on your computer or if you have a converter that lets you plug 2 PS2 gamepads into a single USB port on your computer.

If you have the first option, your devices are NOT operating with any of their USB functionality therefore the speed of the USB port is a non-issue. The best you can do is use a shareware program called ps2rate which can increase your PS2 polling rate. You still wouldn't see performance equivalent to running the gamepad as a real USB device.

If you have the second option, I must admit to never having seen such a monster. A USB device requires some intelligence and I can't see the point of designing a USB device that transfers PS2 data. You can't convert something to USB without some electronics because USB is NOT just another form of serial communication. The device would also be limited to the speed of standard PS2 and be uneffected by ps2rate since Windows wouldn't really know that the USB device is really controlling a PS2 gamepad.

Ah, my apologies. Not being into game consoles for many years, I didn't recognize PSX as PlayStation. I take it this device is useful for people running PlayStation emulators on their PC.

Concerning your original question, there is no USB polling rate in the traditional sense of the term. Most likely a device like this would use USB Interrupt Endpoints to transfer the data. This is the closest method to polling in that the device and its driver request that the OS checks for data at a certain time interval. Unfortunately, Windows makes no promises regarding how well it will follow those intervals and it is often slower than the request. Its success is based on what kind of load is on the system and how realistic the interval was to start with. The best you can do is look for driver updates and hope for the best unless you can figure out how to hack the firmware inside the device. Did you try using two of the single converters? You never know but it might work better that way.