I have the exact setup you describe. IIRC the G400-TV marvel box was not
very well supported under Linux. Just like when you decided to get the
Matrox because of it's superb support under Linux I decided to shell out
the extra $20.00 and get a bt878 off eBay because it's the best supported
chipset
I'm helping a friend choose components for his Freevo box. We have
obtained a G400-TV, I've verified that it works great just like my
G400-DH for framebuffer/mga_vid (after I gave mga_vid.o mga_ram_size=16).
Should I recommend he get a BT878 in addition? The G400-TV has capture
capability (http:/