akcs.dom@vpnet.chi.il.us (Dominick Gatto) (05/06/91)
I'm using a Zenith VGA flatscreen monitor with a paradise VGA card and now it only boots in color about one in 25 times. With another monitor it boots in color all the time. If I boot with the Zenith and it comes up in mono. And then I plug in the other monitor, without rebooting the monitor displays in mono. Then I boot with the other monitor and it comes up in color. Any help will be greatly appreciated.
jb@falstaff.mae.cwru.edu (Jim Berilla) (05/07/91)
In article <2824c147-cb1comp.sys.ibm.pc.hardware@vpnet.chi.il.us> akcs.dom@vpnet.chi.il.us (Dominick Gatto) writes: >I'm using a Zenith VGA flatscreen monitor with a paradise VGA card and now >it only boots in color about one in 25 times. With another monitor it boots >in color all the time. If I boot with the Zenith and it comes up in mono. >And then I plug in the other monitor, without rebooting the monitor displays >in mono. Then I boot with the other monitor and it comes up in color. Any >help will be greatly appreciated. I've had this problem on a few of my Zenith monitors. In all cases, the problem has been with a connector inside the monitor that connects the external cable with the video driver board. Monochrome VGA monitors use only the green video signal. The red and blue signals are not connected. When the paradise card is initialized, it checks to see if the red (or blue? not sure which) video line is terminated. If not, then it assumes that it is connected to a monochrome monitor. The connector in my monitors had more than 25 ohms of resistance accross it. This was enough of an increase over the normal 75 ohms that the board made the incorrect assumption that it was connected to a monochrome monitor. The first monitor was sent back to Zenith for repair. It came back after many months worse that it started. None of my monitors will ever go back to Zenith for repair. I've tried many things to improve the contact on this connector. Squeezing the contacts together helped for a while. Contact cleaner didn't help. "Connector Plus" cleaner and lubricant made it worse. It's a real pain to keep opening the monitor and futzing with this connector. For a few months I just unpluged the monitor when rebooting and put some 75 ohm resistors in the VGA connector until the card was initialized. Then plugged in the monitor and continued. Last weekend, it got to be too much. I finally took the monitor apart and soldered the connector together. It is going to be harder to replace the board if I have to, but at least it boots in color and does not have the annoying color shifts that it used to. SAFETY WARNING: Poking around in monitors is dangerous. If you don't know what you're doing, get a television repairman to help you. -- Jim Berilla / jb@falstaff.cwru.edu / 216-368-6776 "My opinions are my own, except on Wednesday mornings at 9 AM, when my opinions are those of my boss."