No signal with dual monitors (DVI + VGA) w/Matrox G550

[130s]

All,

although there are many threads regarding matrox graphic board screaming out for solutions, I'm still posting my own question since I have less experience in graphics.
Any workaround would be appreciated.

Issue phenomenon)
IP-1. With 2 monitors connected
- Neither monitor seems to show nothing when 2 monitors are connected. DVI one says "No signal".
- Upon booting, DVI one shows BIOS displays. Then after Ubuntu's very 1st image, it stops showing.
- Upon shutting down, both show shutting down status on Ubuntu console in maximum display.

IP-2. With a single monitor (DVI)
- Everything is the same as IP-1 (except for VGA display part)

IP-3. With a single monitor (DVI) while power is on, then connect DVI
- DVI shows nothing
- Monitor Configuration tools seems not detect the newly added DVI

Env) Ubuntu 10.10, Matrox MGA G550 AGP (rev 01) on OEM desktop

Since at least DVI display shows BIOS output, I assume that the issue might not be on graphicCard-monitor side, instead I suspect card-Ubuntu.

Thanks,
Isaac