Solved

No Boot Time Video with DVI

Posted on 2009-05-17
17
581 Views
Last Modified: 2012-05-07
I just converted my computers and monitors over to DVI and I have a KVM switch with DVI and USB for the keyboard and mouse. The keyboard and mouse work fine. I can't see any video until the computer boots into Windows. I can't change the BIOS and I can't do any boot time recovery so this is absolutely unacceptable. I have an IOgear KVM switch and a NVIDIA video cards. one of my computers has a problem with the CD-ROM door opening. I decided to upgrade the video driver and I uninstalled the old one. Now I have no video on that computer. This makes me wonder if were even ready for DVI yet. But all of the new video cards are coming out with it so people must be surviving. I tried bypassing the switch but that didn't solve the problem. A direct video connection to my NEC projector yields the same negative results. I have three computers hooked up to my KVM switch and their video drivers are not more than three weeks old. I'm sure that some of you out there have encountered a similar problem.
0
Comment
Question by:JoshOdom
  • 8
  • 8
17 Comments
 
LVL 28

Expert Comment

by:chilternPC
Comment Utility
do you have a VGA socket on the motherboard?
I would use a vga connector to a screen and see if you can disable anything in the BIOS that may be topping the motherboard booting the video onti DVI  - disable the motherboard VGA if there is one.
maybe its the cable? is it a full DVI cable ?, try reversing the cable ?
0
 

Author Comment

by:JoshOdom
Comment Utility
There is no VGA socket on the motherboard. I got all new parts to build these computers thinking that I was really going to be up to date. :-)  A less than elegant solution would be to run another 50 foot cable to the projector using the projectors VGA port. I could swap it out using a VGA--DVI adapter directly to the computer when needed. I didn't understand what you meant when you said disabling anything in the bios that may be topping the motherboard. I wouldn't know what to look for.  I think the problem is that the signal during the boot cycle is analog and somewhere along the line something is blocking everything but digital. My cable is a 50 foot cat 6 with an Atlona AT - DVI15SRS passive extender at each end to amplify the signal. DVI can't go much more than 15 feet without amplification. Before I got this set up I used a VGA cable from the monitor to the computer with an adapter from VGA to DVI. The adapter transmitted both analog and digital.
0
 
LVL 28

Expert Comment

by:chilternPC
Comment Utility
my monitor is DVI and grahpics card  is and it boots up fine - my cable is a standard length and goes straight into the DVI monitor
as I mentioned it may be the cable - some DVI cables do not run all the signals.
0
 

Author Comment

by:JoshOdom
Comment Utility
You probably have a DVI - I cable. I stands for integrated. These cables transmit both analog and digital. There are parts of my system that only transmit digital - DVI-D.  I'm going to have to explore it some more.
0
 

Author Comment

by:JoshOdom
Comment Utility
I tried an experiment. I connected a 10 foot DVI - D from my computer to an Acer monitor.  Under these circumstances I could see the boot cycle as well as the Windows display. Then I connected a 50 foot cat 6 cable with an Atlona booster at each end terminated by a DVI - D connector, and I saw no display with one computer and just the Windows display on two others. All three had new NVIDIA display adapters.  I will telephone the technical staff at Atlona tomorrow.
0
 
LVL 28

Expert Comment

by:chilternPC
Comment Utility
so the problem is a conversion/booster:
" 50 foot cat 6 cable with an Atlona booster at each end terminated by a DVI - D connector"
not the PC or graphics card
0
 

Author Comment

by:JoshOdom
Comment Utility
the people at Atlona told me that their extenders will not work for the boot cycle and that I am the first one who brought the issue up. They will trade the extenders that I bought for a 50 foot DVI cable that will carry both signals including the boot signal. I don't quite understand the theory behind it but I am willing to give it a try. It should arrive any day.
0
 
LVL 28

Expert Comment

by:chilternPC
Comment Utility
excellent
0
Highfive Gives IT Their Time Back

Highfive is so simple that setting up every meeting room takes just minutes and every employee will be able to start or join a call from any room with ease. Never be called into a meeting just to get it started again. This is how video conferencing should work!

 

Author Comment

by:JoshOdom
Comment Utility
The cable came today. It is 1/2 inch in diameter -- a big heavy thing 50 feet long. But it works. I can see the boot cycle as well as the Windows cycle.
0
 
LVL 28

Expert Comment

by:chilternPC
Comment Utility
in my opinion -  I gave you the answer in my first response
0
 

Author Comment

by:JoshOdom
Comment Utility
Dear chilternPC,

It was so terse I didn't understand it.  What would you look for in the bios?  What is the difference between a full DVI cable and a not full DVI cable?  Write out your post in detail and I'll give you the points.
0
 
LVL 28

Expert Comment

by:chilternPC
Comment Utility
hi JockoDom,
I'm sorry if you found the suggestions "terse"   - to help you decide I'll reprint my comments from the previous responses (see above):

 my first helpful suggestion:  "maybe its the cable? is it a full DVI cable ?, "
My second helpful comment : "as I mentioned it may be the cable - some DVI cables do not run all the signals."
you then reported back that you tried an experiement with a full cable and it all worked.  I assume I helped you get to an answer.


0
 

Author Comment

by:JoshOdom
Comment Utility
OK, I see your point.  But it was the people at Atlonis that gave me more information that solved the problem for me. Would you be willing to enlighten me regarding the difference between the different kinds of cables and the things that you would look for in the bios.  If you will do this I'll give you the points.
0
 
LVL 28

Expert Comment

by:chilternPC
Comment Utility
no worries.. the 3 types of DVI  interface:  DVI-integrated are DVI-Analog and DVI-Digital and depending on what devices you have at either end you can use the correctly designed cable:

1) DVI-D - True Digital Video
DVI-D cables are used for direct digital connections between source video (namely, video cards) and digital LCD (or rare CRT) monitors. This provides a faster, higher-quality image than with analog, due to the nature of the digital format. All video cards initially produce a digital video signal, which is converted into analog at the VGA output. The analog signal travels to the monitor and is re-converted back into a digital signal. DVI-D eliminates the analog conversion process and improves the connection between source and display.
2) DVI-A - High-Res Analog
DVI-A cables are used to carry a DVI signal to an analog display, such as a CRT monitor or budget LCD. The most common use of DVI-A is connecting to a VGA device, since DVI-A and VGA carry the same signal. There is some quality loss involved in the digital to analog conversion, which is why a digital signal is recommended whenever possible.
3)DVI-I - The Best of Both Worlds
DVI-I cables are integrated cables which are capable of transmitting either a digital-to-digital signal or an analog-to-analog signal. This makes it a more versatile cable, being usable in either digital or analog situations.
Like any other format, DVI digital and analog formats are non-interchangeable. This means that a DVI-D cable will not work on an analog system, nor a DVI-A on a digital system. To connect an analog source to a digital display, you'll need a VGA to DVI-D electronic convertor; to connect a digital output to an analog monitor, you'll need to use a DVI-D to VGA convertor.
for more info see: http://www.datapro.net/techinfo/dvi_info.html#Page06

for more detail on the BIOS - sometimes the onboard graphics card gets 'boot to' first before realising there is another graphics card and so the theory being the boot dispaly was being shown on the onboard graphics display and switching over once windows had loaded. if this were the case then my suggestion would be to go into the BIOS and disable the onboard graphics - exact details are dependant on your motherboard and would be documentated in the motherboard userguide.




0
 

Author Comment

by:JoshOdom
Comment Utility
With regard to the cable, I am aware of what you just told me. The cable ends are the digital type with the -- instead of the cross. The cable that I had before that didn't work was also digital, with the --. The only difference that I can see between the two is that the cable that works is 1/2 inch thick -- much larger than the other one. The issue here is what qualities of the cable are related to its ability to go to 50 feet instead of 15 feet. The cable is not a DVI-I cable.
0
 
LVL 28

Accepted Solution

by:
chilternPC earned 500 total points
Comment Utility
this is now going in the direction of a  new question.
I think you  have a solution to your original problem

Please refer to following link for more details about how to close a question.
http://www.experts-exchange.com/help.jsp?hi=407


0

Featured Post

How your wiki can always stay up-to-date

Quip doubles as a “living” wiki and a project management tool that evolves with your organization. As you finish projects in Quip, the work remains, easily accessible to all team members, new and old.
- Increase transparency
- Onboard new hires faster
- Access from mobile/offline

Join & Write a Comment

Microsoft Office Picture Manager was included in Office 2003, 2007, and 2010, but not in Office 2013. Users had hopes that it would be in Office 2016/Office 365, but it is not. Fortunately, the same zero-cost technique that works to install it with …
Let’s list some of the technologies that enable smooth teleworking. 
The goal of the tutorial is to teach the user what gradient filters are and how to use them. When you have a photo and some part of the photo is either over exposed or under exposed, you use a gradient filter to help mask the need to touch up th…
The goal of the tutorial is to teach the user the full work flow of how to use flash media encoder to stream onto YouTube.

771 members asked questions and received personalized solutions in the past 7 days.

Join the community of 500,000 technology professionals and ask your questions.

Join & Ask a Question

Need Help in Real-Time?

Connect with top rated Experts

10 Experts available now in Live!

Get 1:1 Help Now