1. Welcome to TechPowerUp Forums, Guest! Please check out our forum guidelines for info related to our community.

Now, A Dongle That Converts D-Sub to HDMI and Vice Versa

Discussion in 'News' started by btarunr, Nov 6, 2012.

  1. btarunr

    btarunr Editor & Senior Moderator Staff Member

    Joined:
    Oct 9, 2007
    Messages:
    28,531 (11.25/day)
    Thanks Received:
    13,641
    Location:
    Hyderabad, India
    If you're feeling the pinch of lack of HDMI inputs on their monitors, you'll find this little dongle from the bi-lanes of Tokyo's Akihabara shopping district handy. The TEC HDCOM-001, as it's called, has a male D-Sub connector on one end, which plugs into the D-Sub connector of your monitor, and an HDMI input. The HDMI connection can carry both video to the monitor and up to 6 channels of audio, which are given out by the dongle as analog audio outputs. The gadget could come handy when pairing Ultrabooks (which lack D-Sub, and provide HDMI) with analog monitors, or those which lack HDMI inputs. It can also be used the other way, to convert D-Sub to HDMI, using an included male to female cable. Its DAC supports display resolutions as high as 1920 x 1080, with 60 Hz refresh rate. Measuring 41 x 72 x 18 mm, it weighs about 120 g. It is priced at 5,480 JPY (US $68).

    [​IMG] [​IMG] [​IMG]

    Source: Hermitage Akihabara
     
  2. LAN_deRf_HA

    LAN_deRf_HA

    Joined:
    Apr 4, 2008
    Messages:
    4,540 (1.93/day)
    Thanks Received:
    938
    I don't get it. Why is a dvi to vga adapter so simple but a hdmi to vga a big deal?
     
  3. M3T4LM4N222

    M3T4LM4N222 New Member

    Joined:
    Dec 21, 2009
    Messages:
    144 (0.08/day)
    Thanks Received:
    10
    Looks like it also carries audio.
     
  4. Jetster

    Jetster

    Joined:
    Jan 17, 2010
    Messages:
    4,954 (2.91/day)
    Thanks Received:
    1,992
    Location:
    Oregon
    D sub or VGA is analog, DVI and HDMI are digital. So you cant just connect them together without converting the signal
     
  5. agent00skid

    Joined:
    May 6, 2012
    Messages:
    546 (0.63/day)
    Thanks Received:
    355
    There are 3 types of DVI.

    DVI-D: Digital signal only.
    DVI-A: Analog signal only.
    DVI-I: Digital and analog signal.

    And then the digital signal can be single or dual link.

    The digital signal is compatible with HDMI and the analog is compatible with VGA/D-sub15.
     
    Crunching for Team TPU
  6. LAN_deRf_HA

    LAN_deRf_HA

    Joined:
    Apr 4, 2008
    Messages:
    4,540 (1.93/day)
    Thanks Received:
    938
    None of that really addresses it. Why is it so easy for dvi to convert analog but hdmi can't do the same? I've always seen it explained that dvi and hdmi send the same digital signal in different connectors, hdmi just having the added audio ability which is unessential. So why can't hdmi get a similarly small and cheap vga adapter as dvi?
     
  7. Tarkhein

    Joined:
    Aug 3, 2011
    Messages:
    47 (0.04/day)
    Thanks Received:
    13
    DVI has analog pins, HDMI does not.
     
  8. agent00skid

    Joined:
    May 6, 2012
    Messages:
    546 (0.63/day)
    Thanks Received:
    355
    Well, for DVI-I there already are provisions for analog, so a DVI-I to VGA is just a rewiring.

    HDMI doesn't have any provisions for analog in any form, so for that to happen, a DAC or ADC is need to convert from one to the other.
     
    Crunching for Team TPU
  9. SaltyFish

    SaltyFish

    Joined:
    Jun 6, 2012
    Messages:
    324 (0.39/day)
    Thanks Received:
    84
    The common adapters are passive and work the following way:
    DVI-D <-> HDMI
    DVI-A <-> VGA

    Note the digital/analog thing... you can't go VGA <-> DVI <-> HDMI without some sort of active adapter somewhere. That's what this thing pretty much is.

    EDIT: Passive is simply a re-wiring... just a connector with no need for power. Active takes the signal and does some processing on it. Note the need for a power supply.
     
    Last edited: Nov 6, 2012
  10. Mussels

    Mussels Moderprator Staff Member

    Joined:
    Oct 6, 2004
    Messages:
    42,207 (11.62/day)
    Thanks Received:
    9,511
    you dont convert it, normally. DVI sockets *include* VGA pins, that the adaptors use to output a native VGA signal.


    thats why there are variants like DVI-I and DVI-D, some of them are digital only, and dont carry those signals.



    This is a true conversion - HDMI w/ 5.1 to analogue audio/VGA, or the other way around.
     
  11. RejZoR

    RejZoR

    Joined:
    Oct 2, 2004
    Messages:
    4,606 (1.27/day)
    Thanks Received:
    918
    Location:
    Europe/Slovenia
    Most VGA cards have DVI-I so you only have to place an adapter on it to change the shape of the connector. In case of HDMI, you don't have any analog fallback to use. It's fully digital signal. So if you want to get VGA or SCART out of HDMI, you need to have a special electronic converter that actually converts the signal into analog and forwards it to some older type of connector (VGA/SCART). There is no way of bypassing that.
     
  12. eidairaman1

    eidairaman1

    Joined:
    Jul 2, 2007
    Messages:
    12,387 (4.70/day)
    Thanks Received:
    1,453
    ya via DVI-I to VGA Out Adapter
     
  13. 3870x2

    3870x2

    Joined:
    Feb 26, 2008
    Messages:
    4,875 (2.04/day)
    Thanks Received:
    689
    Location:
    Joplin, Mo
    I just heard he same explanation about 6 times. One would probably do. But while we are at it,

    DVI-I includes pinouts for both analog and digital, thus making the conversion straight-through.

    DVI-D is not actually compatible with a DVI-VGA adapter. DVI-A (rarely seen) is analog only.
     
  14. racedaemon

    racedaemon

    Joined:
    Feb 23, 2012
    Messages:
    43 (0.05/day)
    Thanks Received:
    2
    As i understand it a DVI-I plug has behind it a DAC built in on the video card as the signal from the video card is originally digital. So this external device is what should have been on the video card/motherboard and it has presumably the same circuitry.

    Off topic: Why the hell are they putting on motherboards combinations like: VGA + DVI + HDMI or VGA + HDMI or HDMI + DVI?! Jut put a single DVI-I connector and give us USB 3 in the remaining space or another LAN jack!
     
  15. Chevalr1c

    Chevalr1c

    Joined:
    Sep 3, 2010
    Messages:
    3,202 (2.17/day)
    Thanks Received:
    1,383
    Location:
    NL, Europe
    If people want to attach the matter to their TV through HDMI, DVI-I (or DVI of any kind) is useless becaue the sound signal meets a dead end (meaning the need for seperate speakers). So at least DVI-I and HDMI are required.
     
    Crunching for Team TPU
  16. Frick

    Frick Fishfaced Nincompoop

    Joined:
    Feb 27, 2006
    Messages:
    10,585 (3.39/day)
    Thanks Received:
    2,214
    Also multiple outputs are always nice.
     
    Chevalr1c says thanks.
  17. FordGT90Concept

    FordGT90Concept "I go fast!1!11!1!"

    Joined:
    Oct 13, 2008
    Messages:
    13,551 (6.26/day)
    Thanks Received:
    3,492
    Location:
    IA, USA
    DVI has VGA + digital. HDMI is just DVI's digital (they removed backwards compatibility with VGA). A VGA -> HDMI has to encode analog to digital or decode digital to analog in order to make the conversion. The problem with that it is it has to be real-time to not create lag.


    Looks like it does component video and optical audio too.
     
    Crunching for Team TPU
  18. racedaemon

    racedaemon

    Joined:
    Feb 23, 2012
    Messages:
    43 (0.05/day)
    Thanks Received:
    2
    It is not exactly useless, you could use a SPDIF cable for audio, but it would be a hassle and lack elegance.

    I was too broad in my statement, i was thinking about desktop computers not HTPCs. On a "workstation", that has a dedicated video card with all the video connectors, you would use the motherboard's video connectors only for backup or some sort of dual display. In this situation a greater number of USB ports or an extra NIC is more desirable than three video connectors you wouldn't use frequently.

    On a HTPC you definitely need HDMI.

    As for VGA on any type of motherboard instead of a DVI-I... I'm baffled and annoyed by such occurrence.
     
  19. Mussels

    Mussels Moderprator Staff Member

    Joined:
    Oct 6, 2004
    Messages:
    42,207 (11.62/day)
    Thanks Received:
    9,511
    that part, i agree with.
     
  20. johnashdown123 New Member

    Joined:
    Nov 11, 2012
    Messages:
    1 (0.00/day)
    Thanks Received:
    0
    DVI and HDMI are digital signals and VGA is analog. If you are looking to do a true digital to analog signal conversion you will need an active converter box as adapter won't work. I had a couple of applications like these and ended up buying DVI-D to VGA and HDMI to VGA converters from KVMSwitchTech and they work great.
     

Currently Active Users Viewing This Thread: 1 (0 members and 1 guest)

Share This Page