Are the 7941G-GE phones different than the 7941G on how the startup works? Plug in the 7941Gs and they automatically run the startup, plug in the 7941G-GE and get no startup. Do they need a separate power supply to work?
Yes, they power requirement for a 7941 and 7941-GE are not the same. 7941 works with Cisco Pre-standard PoE and with IEEE 802.3af PoE.
http://www.cisco.com/en/US/customer/products/hw/phones/ps379/products_data_sheet0900aecd802ff012.html (Please Check Power Requirements)
9741-GE Phones only supports IEEE 802.3af PoE. If your Switch does not support 802.af then you can use the AC-to-DC power supply (part number CP-PWR-CUBE-3=).
(Please Check Power Requirements)
As quoted by Mahesh, the 7941 and the 7941-GE are not the same and they should work on a switch that supports both (Cisco pre-standard and IEEE) PoE standards.
You can also buy a power brick for those phones if the you dont have a switch that supports that phone PoE standard.
This is the power brick part number: CP-PWR-CUBE