Hi retro, I don't know for sure, but it could be that the card supports EGA with borders (640x350 centered in 640x400 res).
If it still runs in EGA's 60Hz mode is another thing. VGA's 200/400 lines mode runs in 70Hz normally.
On the other hand, the card could also be configured for an analogue multi-sync with 100& EGA timings.
Hard to say. 🙁
Anyway, I remember another thread about ATI VGA Wonder+:
ATI VGA Wonder+ No Video Out
Maybe some of the manuals lnked are helpful in answering some of the questions. 😀
Since I neither had a ATI Wonder+, nor its mode utilities (if it had some), I can only say very little about it.
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In what to one race is no time at all, another race can rise and fall..." - The Minstrel
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