If you take a look at the motherboard, can you find any chips by Chrontel or Silicon Image? Combined with that chipset, I'd expect maybe a Chrontel CH7317, which is a mere level-converter for the low-voltage HDMI-framed native outputs of the GMCH. Consequently, your HDMI output might be HDMI-B or HDMI-C (I believe).
Are you using the CED utility to try to configure the driver?
This is a GM45 chipset so your DVI output could be either an sDVO transmitter, or driven directly off the internal capability.
The key for "DVI" support is knowing which PORT the DVI is being driven from B or C for either internal or sDVO. Likely it will be port B for either. If the internal capability is being used, the key to support that with IEGD should be to specify HDMI (HDMI-B) as HDMI and DVI use very similar signaling.
To get auto-detection of a display, you need to be sure to use all displays that have EDID. To skip a non-detected display you need to set the "Display Detection" option for the port. IMPORTANT: LVDS has no way to detect presence or if it is missing so it is always assumed to be attached no matter what. Thus, to get this to work, you would need to either put the port order to HDMI-B, CRT, then LVDS and if a CRT and and DVI is plugged in, the LVDS will not be selectable even if it is present. However, if either the DVI (hooked to the HDMI port) or CRT are absent, then LVDS will be assumed to be hooked up.
If your platfrom uses sDVO to drive the DVI, then thes same applies, just replace HDMI with sDVO in the config.
Hope this helps.
Thank you all for your suggestions.
I was unable to find any Chips that matched the ones you mentioned, I however did find a Parade PS8101T "
HDMI/DVI Level Shifter for AC Coupled Source Device
Is it fairly safe to conclude I cannot use the IEGD?
Thank you all again
A level shifter is PAST the point where the driver cares so the use of that particular level shifter should not be an issue. It sounds like this situation is being driven from the internal HDMI. A careful organization of the ports and the use of "display detect" with IEGD should be able to handle this situation.
In the past on the GM45, there has been confusion over the port numbers used for what feature.
Fundamentally, with some experimentation, you should be able to get it all going.