From Brad Parker (out among the flat cornfields of
Note the original unit has [heat] shrink tubing on the resistor leads - Not a bad idea. An alternate technique would be to just plug in any old monitor on the base video VGA output. Of course that takes up a bit of physical desktop.
Will The Real ATI GUP
Terminator Stand Up?
The resistors provide a simulated load to
the RGB signal
circuits, a condition apparently required by the
M-Motion Adapter. Brad
thinks that this terminator may also work to satisfy the
ATI GUP logic
This, in fact, may not be so.
In stark contrast,
I checked the terminators supplied with the ATI
Graphics Ultra Pro
16-bit ISA and MCA versions, and they are identical.
They are wired like this:
In words, the system still thinks that an 8512/3 display is attached, but that the color signals are shorted to their respective grounds. I have no idea what the system or GUP logic decides about this. Maybe the 75-ohm load terminator and the dead-shorted terminator may be interchanged. Maybe not. There is an easy way to find out. QED.
Peter Fires Back
Usually the card is designed to work
as "2 cards
/ 2 screens" solution. Under e.g. AutoCAD the normal VGA
displays the texts
and help screens, while the Gemini only displays the
hi-res graphics using
a Fixed frequency monitor.
Assumed you have a multisync monitor you could attach this to the Gemini and plug the terminator to the standard VGA. The Gemini/2 has VGA Loop Through capability without additional components, while the other (ISA/EISA) Geminis require a VGA feature connector cable or the Gemini VGA loop through Add-On board (Rem: the Gemini/2 uses the AVE connector on the MCA). With the GMISETUP the card must be configured as VGA loop through / single screen installation. That's all.
Personally I want to add that a *short circuit*
(Null Ohm) between
any of the RGB color signals and their according GND
returns is a bad idea.
I would not recommend to use a "plug" that shorts
the video card
outputs to GND with no resistor between. This could
cause damage of the
video output drivers ... and if that video card is a
planar-Video you will
probably need a new board afterwards.