I need 24v with atleast 2A current, i have a couple of pc power supplys sittings arround that can deliver more then 2amps on the 12v rail. Is it safe to connect the two powersupply's 12v rail in series to get 24v? on one power supply connect the ground from the molex to the yellow on another, then take the 24v from ground and yellow? Is this safe, or am i going to run into trouble if i try this? Thanks.