Wait, the monitor does not have a DVI port, an HDMI port, or a VGA port?
The only other option I think the monitor could have is S-Video or composite, which would be astounding if that's the case. You can use a HDMI-DVI converter from your RasPi to get out to DVI, then a DVI to VGA converter to get to VGA, but I'm not aware of a VGA to S-Video or composite converter.
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Wait, the monitor does not have a DVI port, an HDMI port, or a VGA port?
The only other option I think the monitor could have is S-Video or composite, which would be astounding if that's the case. You can use a HDMI-DVI converter from your RasPi to get out to DVI, then a DVI to VGA converter to get to VGA, but I'm not aware of a VGA to S-Video or composite converter.