I'm curious about my MStar ISP upgrader.

[Axle Grease]

What does the switch do?

What do the red, yellow, and green LEDs signify?

What is the purpose of the three 4-pin headers? A small ribbon cable arrived with the unit and fits into the middle header and is terminated at one end only.

Why are there two VGA connectors?

Can this upgrader be used on other monitors and, if so, where would I find a compatibility list?

[Chief Blur Buster]

What does the switch do?

What do the red, yellow, and green LEDs signify?

What is the purpose of the three 4-pin headers? A small ribbon cable arrived with the unit and fits into the middle header and is terminated at one end only.

Why are there two VGA connectors?

Can this upgrader be used on other monitors and, if so, where would I find a compatibility list?

The four pin, I think is the JTAG ICE header, used for In-Circut Debugging.
One VGA is an input connector, and the other is an output connector, as I understand it.
Not sure of LEDs, but I know one of them is a DATA indicator.

Yes, it is used for upgrading HDTVs and monitors at the factory. Instructions are hard to come by and most use easier firmware upgrade methods. But the Z-Series is the only consumer 120Hz monitor that is upgradeable by consumers. It was not intended to be upgradeable, but the Version 2 firmware situation (the artifact in blur reduction mode) pushed things forward, so that users have a choice.

[Axle Grease]

Thank you, Chief.