I'm not sure if this is old news by now (I haven't been reading the forums as much as before, forgive me ) but it looks like we have proof from Matrox that the G400 Marvel exists.
From the Install.inf file of Powerdesk 5.21.017:
Str0="Matrox G200 Multi-Monitor"
Str1="Matrox G400 AGP"
Str2="Matrox MGA-G100 AGP"
Str3="Matrox MGA-G200 AGP"
Str4="Matrox Marvel G200 AGP"
Str5="Matrox Marvel G200 PCI"
Str6="Matrox Marvel G400 AGP"
Str7="Matrox Millennium G100 AGP"
Str8="Matrox Millennium G200 AGP"
Str9="Matrox Millennium G200 LE AGP"
Str10="Matrox Millennium G200 SD AGP"
Str11="Matrox Millennium G200 SD PCI"
Str12="Matrox Millennium G250 AGP"
Str13="Matrox Millennium G250 LE AGP"
Str14="Matrox Millennium G400"
Str15="Matrox Millennium G400 Dual Head"
Str16="Matrox Millennium G400 Dual Head Max"
Str17="Matrox Mystique G200 AGP"
Str18="Matrox Mystique G200 Video AGP"
Str19="Matrox Productiva G100 AGP"
Str20="Matrox Productiva G100 Multi-Monitor"
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Mark Veneziano
From the Install.inf file of Powerdesk 5.21.017:
Str0="Matrox G200 Multi-Monitor"
Str1="Matrox G400 AGP"
Str2="Matrox MGA-G100 AGP"
Str3="Matrox MGA-G200 AGP"
Str4="Matrox Marvel G200 AGP"
Str5="Matrox Marvel G200 PCI"
Str6="Matrox Marvel G400 AGP"
Str7="Matrox Millennium G100 AGP"
Str8="Matrox Millennium G200 AGP"
Str9="Matrox Millennium G200 LE AGP"
Str10="Matrox Millennium G200 SD AGP"
Str11="Matrox Millennium G200 SD PCI"
Str12="Matrox Millennium G250 AGP"
Str13="Matrox Millennium G250 LE AGP"
Str14="Matrox Millennium G400"
Str15="Matrox Millennium G400 Dual Head"
Str16="Matrox Millennium G400 Dual Head Max"
Str17="Matrox Mystique G200 AGP"
Str18="Matrox Mystique G200 Video AGP"
Str19="Matrox Productiva G100 AGP"
Str20="Matrox Productiva G100 Multi-Monitor"
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Mark Veneziano
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