The Matrox TVO controller on-board the Marvel G400 is the same chip used on the Millennium G400 boards and provides for the DualHead functionality of the card. For those of you unfamiliar with DualHead, it is the ability to use the single G400 graphics chip to output to two separate output devices as if it were two separate graphics cards. Absent from the Marvel G400 is the second VGA output connector like that found on the other two G400 boards. Instead it has been replaced by the 26-pin proprietary connector that is used to interface with the Marvel's breakout box.
This effectively cripples the DualHead functionality as we've come to know it on the Marvel G400. However, with the use of a soon to be available daughter card, the second interface provided for by the DualHead will offer the option of being a Digital Flat Panel (DVI) connector.
So, although the Marvel G400 makes use of the DualHead feature, the secondary output can go to either a TV screen using the Marvel's breakout box or a Digital Flat Panel monitor with the optional daughter card. Keep in mind that this additional daughter card occupies a slot cutout to the right of the Marvel G400 and thus removes a single PCI slot from being available in your system.
The breakout box is virtually identical to the old Marvel G200's breakout box. The same no-slip-grip feet on the bottom of the box make setting it on the floor or on your desk a simple task and you don't have to worry about it sliding around too much. One complaint about the design is that it is still the bulkiest in comparison to the boxes of its two biggest competitors (AIW128 & 3500TV). The breakout box still features the three composite inputs and outputs, as well as the S-Video inputs and outputs and the Coaxial Cable/Antennae input.
The only new addition to the Marvel G400's breakout box is the SPDIF output connector for digital sound output. While this is a unique addition to the Marvel G400, we didn't see any real purpose other than for outputting digital sound for DVD playback.