Does  my DVI-I connector have any blanking time overhead?

Posted on 2007-07-25
Last Modified: 2013-11-08
I have a Radeon 9000 pro card. The card has both a DVI-I connector, and a VGA connector. I have it connected to a LCD monitor using a DVI-I cable that's connected to the DVI-I connector on the card.

How am I to understand the data that's going thru this connector. I have two choices:

* I assume that since the connector is DVI-I, it will have support for a VGA monitor, and therefore if I reduce the blanking overhead of the card, I'll improve the card's performance.


* I assume that since the card has both a VGA connector and a DVI-I connector, that the DVI-I connector will have no blanking overhead, since the manufacturer of the card will be assuming that anyone who is going to use the card with a VGA monitor, will simply use the VGA connector.

Which of these is correct?

Thank you
Question by:shlomofu99
    LVL 32

    Expert Comment

    LCD monitors don't have electron beams like CRT's so there is no Blanking overhead involved, but the DVI signal still holds onto this blanking overhead in case you use an analog signal for a CRT on the card.
    This page gives an abundance of info on the subject, scroll down to the REDUCED BLANKING section .

    Author Comment

    Thanks, Sparkmaker

    Yes, I'm familiar with that website. I went thru it carefully. Please understand what I'm asking:

    This card has two ports, i.e. two places I can plug a monitor cable into. There is one for a VGA monitor, and one for a LCD monitor. The latter port is a DVI-I port, meaning it can handle both analog and digital. Why would Sapphire, the maker of the card, built support for a CRT into a DVI port, if right next to it is a VGA port that people who have a CRT will use? Perhaps they didn't do this, and the DVI-I port is really working like a DVI-D port?

    It just doesn't make sense to put a DVI-I port there. I expected to see a DVI-D port there, not a DVI-I one

    LVL 32

    Accepted Solution

    Its all about options.
    DVI-I will output both analog and digital, whether its single or dual link is another matter. The reason for both is diversity for dual monitor application and diversity in analog or digital output.
    You can also buy dual DVI-I cards without the VGA connector but they will also allow the usage of a DVI-I to VGA adapter as your card will. The only truly Digital card will have the DVI-D output and that will only output a digital signal.

    Author Comment

    Thank you very much. I get it now. Dual monitor application - that was the key that I had missed.

    I appreciate your helping me.

    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

    Suggested Solutions

    System overheating may become a serious problem if not taken care of at the proper time. I am writing this article because I faced a similar problem. Intro All electronic devices produce heat, but computers are a special case - the processors bo…
    This video is in connection to the article "The case of a missing mobile phone (". It will help one to understand clearly the steps to track a lost android phone.
    Polish reports in Access so they look terrific. Take yourself to another level. Equations, Back Color, Alternate Back Color. Write easy VBA Code. Tighten space to use less pages. Launch report from a menu, considering criteria only when it is filled…

    754 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

    20 Experts available now in Live!

    Get 1:1 Help Now