I have a Gateway DX4200 with a Liteon PS-6301-08A 300 watt PSU and was just given a OCZ Stealth X stream 700 watt PSU Can i replace my 300 watt PSU with the OCZ one, will it fit my motherboard this is the MoBo Gateway Acer Foxconn Bengal RS780 Motherboard 4006272R
PSUs don't need to fit in a motherboard, but they do need to fit in your case. Since you already have it in hand, just give it a try.
So if it fits in the case it will work for the MoBo??