Thanks to all for the info; especially ALK for the links. The spaces labeled 250....400 have nothing soldered in, but the speed resistor matrix elsewhere indicates this is a 300Mhz board. I got this to install in the 9500 I'm hopefully getting from Orion, but maybe a 8600 or 9600 will come this way one of these months. Sigh! Only paid $11 for it, so no big deal at this point.