You'd think it would be a simple termination issue, but... a little while back, I helped a buddy out with a GVP A590 like device and sure as ****, you *did* need a HD installed in order for the pass-thru to work. Not 100% sure if not having a HD installed would refuse the computer to boot, but then again, there's an "on-off" switch on the GVP that bypasses the HD and allows it to boot. "Game mode" they call it. Wouldn't be surprised if hooking a harddriveless A590 to an A500 without such a switch would cause the computer to hang. I doubt you'd have two "bad" A590's, so throw a HD in there to be absolutely sure!
