
I think you will find the HUB dose not have enough power to run 24 gridseeds
what size is the PSU?
This is the Monoprice 24-port USB hub. I don't have it in front of me right now, but I think the power adapter for it is 12V at 4A = 48W. The Gridseeds are powered using 12V at 7A = 84W power bricks. Each one powers 8 Gridseeds each, and the Gridseeds run in scrypt only mode. I purchased the 20x Gridseed kit from Zoomhash, 4 of them.
i'm not sure but i dint think thats enough power on the 5v Line to power all the gridseeds.