The fastest sampling rate that the GM/GX/GP series can achieve is a 1msec update rate. This can only be done using the GX90XA-HO high speed module, and only one of those channels can be used at this sampling rate. It does not matter how many of the GX90XA-HO modules you have, the GM/GX/GP series can only have one channel at 1 msec update rate at a time.
Yokogawa data acquisition systems give you the most flexibility and power to measure, display, store, and even actuate any number of physical or electrical phenomena.