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One may buy a simple HDMI-to-VGA cable, or an HDMI-to-DVI cable. Example: on Amazon. However, my vague knowledge is that these cables only work for video cards that have special support for this function. Does the Raspberry Pi support such things?

Is there any easy way to use the Raspberry Pi on a screen that only takes VGA input without a converter box? What kind of conversion to other video outputs would the Raspberry Pi hardware support, and what cables or other equipment would be necessary for this?

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    I remember reading somewhere on Wiki that passive HDMI-DVI adapters should work but HDMI-VGA requires an active converter.
    – user13
    Commented Jun 13, 2012 at 14:51
  • Would a composite-VGA be a better option?
    – Alex Chamberlain
    Commented Jun 13, 2012 at 15:48
  • I think the product you linked to is designed to connect a PC's VGA output to a monitor's HDMI input, i.e. the opposite direction to what you want.
    – finnw
    Commented Jun 13, 2012 at 16:01
  • I think I'm finding a lot of products incorrectly sold as a HDMI to VGA cable, although as @finnw points out, a closer reading of the specs shows that this is backwards. This helps to clear up the situation. More expensive true converters can be found.
    – AlanSE
    Commented Jun 13, 2012 at 16:29
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    @Jivings - That's odd, HDMI is just single link DVI-D with a different connector. Are you sure it's not your monitor failing to sync to the resolution used by your RPi?
    – Mark Booth
    Commented Jun 14, 2012 at 10:15

7 Answers 7

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No.

The reason a DVI-to-VGA adapter works on your PC & laptop is that DVI includes analog (RGB) pins. The adapter is passive; It just connects the red analog output of the PC to the red analog input of the monitor, ditto for green and blue. They are included on most PCs and laptops for backward compatibility.

HDMI-to-DVI cables are also passive, but they carry digital signals only. The analog RGB signals are missing, but that does not matter as the DVI monitor does not need them.

HDMI contains no analog signal so it is not possible for any combination of passive adapters and/or cables to convert it to VGA.

Active adapters work because they use DSPs and DACs to convert from one standard to the other, but of course they are more expensive than passive cables.

Related forum thread: http://www.raspberrypi.org/phpBB3/viewtopic.php?f=30&t=8125

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  • Good answer, want to select it. One small bit: what is an HDMI to VGA cable and why will it not work with the Raspberry Pi?
    – AlanSE
    Commented Jun 13, 2012 at 15:50
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    @AlanSE, dedicated HDMI to VGA cables will work, as they contain the necessary circuitry. But I assumed that was not what you meant because you said "simple cable."
    – finnw
    Commented Jun 13, 2012 at 15:51
  • What I meant is a simple cable like the one I linked to in the question. This cable does not contain the necessary circuitry. It works for some graphics cards and people are going to keep being confused about it unless it's clear what makes those different and why that does not apply for the Raspberry Pi.
    – AlanSE
    Commented Jun 13, 2012 at 15:54
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    @AlanSE - The important thing about that Amazon item is the NOTE: Your Video card must support digital signal output through VGA port function. I don't know of any video cards which support outputting VGA over pins of a HDMI connector, and a quick google search couldn't find any.
    – Mark Booth
    Commented Jun 14, 2012 at 10:21
  • Got a TV receiver that has a passive VGA trough HDMI mode, guess it just puts VGA signals trough the cable with an HDMI connector on one end and a VGA connector on the other.
    – axk
    Commented Aug 15, 2018 at 22:08
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The Neewer HDMI to VGA converter lead from Amazon does indeed work with the RPi but as has been reported elsewhere you have to do a bit of fine tuning in the /boot/config.txt file.

I still cannot get my Samsung 943N to see anything but a simple Dell generic 15" VGA monitor works fine. One problem seems to be that the default output signal level is not sufficient so setting config_hdmi_boost=4 seems necessary. The monitor also complains that it wants 1024x768 at 60Hz which is hdmi_mode=16.

The article at http://elinux.org/RPi_config.txt also suggests that the hdmi_group values documented should be 0 and 1 not 1 and 2 and indeed I needed to change hdmi_group to 1. So my current file looks like:

hdmi_drive=2 
config_hdmi_boost=4 
hdmi_group=1 
hdmi_mode=16 
hdmi_force_hotplug=1 
disable_overscan=0

Modification for Dell 15" Monitor with Debian GNU/Linux 6.0 OS I found that it would only work with: hdmi_group=2

Raspberry Pi User Guide by Eben Upton has the video modes in the appendix. The user guide lists the hdmi_group values as 1 or 2.

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  • You write that it needs some tuning? Does it need that in order to work at all, or does it need the tuning just to get a better picture? I am trying to connect my laptop/Raspberry to a monitor with a similar active adapter, and there is simply no connection.
    – Mads Skjern
    Commented Feb 11, 2014 at 21:09
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The "simple" HDMI to VGA cables will not work quite simply because HDMI signals are pure digital and VGA is analogue. I made the mistake of buying a very cheap cable from Amazon which did not work for reasons that are clear to me now. I am awaiting the delivery of a "Neewer Black HDMI Input To VGA Adapter Converter For PC Laptop" from Amazon which I am confident will do the job. It was less than £15. I will post my findings here.

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    Has that 'cable' arrived yet? It has been some years now....
    – Hennes
    Commented Dec 12, 2017 at 18:15
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I am using this cable to connect my Raspberry Pi to an HP monitor (with DVI input).

A couple of notes: You can not then connect another cable or adapter to change this to a VGA input. Secondly, if converting the Raspberry Pi's HDMI to DVI be careful of the DVI connector; there is more than one type and one size does not fit all (I learned this lesson the hard way).

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  • What type of DVI input did you have (like DVI-D) and was it a single link or dual link cable? I have an HP monitor myself and will need to get a cable for it. Is the selection based entirely on the monitor, or does the RasPi HDMI specs have anything to do with it?
    – AlanSE
    Commented Jun 13, 2012 at 20:00
  • @AlanSE The DVI adapter was a DVI-I, and the monitor wanted a DVI-D. The specs for the pi had nothing to do with it simple problem of pin/connector geometry. The cable I linked to in my answer works like a charm and was far cheaper than most local alternatives even with the expedited shipping included.
    – Steve Robillard
    Commented Jun 13, 2012 at 20:09
  • I still don't understand something. Why would you get a DVI-I adapter? And since the cable to your DVI monitor should have a male connector, and since the DVI-I has more connections than the DVI-D, you shouldn't physically be able to plug it in. The Amazon link you give isn't clear in the description, but the picture looks like DVI-D. This discussion might be better suited for a DVI question, but I'll see about giving an update when I do this myself.
    – AlanSE
    Commented Jun 14, 2012 at 15:59
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It may be a problem with your configuration file. Try deleting it, and if that doesn't work try changing it to this.

# config.txt
hdmi_group = 2
hdmi_mode  = 4

A list of available properties for the Raspberry Pi can be found here.

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  • Why is this downvoted?
    – user46
    Commented Jun 13, 2012 at 15:19
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    probably because it will not work. The OP is (if I understand correctly) asking about a combination of a HDMI->DVI cable and DVI->VGA adapter. Your solution will work only for a DVI monitor.
    – finnw
    Commented Jun 13, 2012 at 15:42
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    I had in mind more of HDMI->VGA as opposed to HDMI->DVI->VGA although that's not important. Your claim that it can use a DVI monitor with passive cables is useful and relevant to the question, as well as the claim that it can not work with a VGA monitor without conversion equipment. I think we are close to consensus on that.
    – AlanSE
    Commented Jun 13, 2012 at 15:48
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It is important to not just give up when the adaptor/converter doesn't seem to work out of the box. Most probably there will be converters which won't work and VGA displays which won't be supported, but my feeling is most of them work just fine - with some extra steps.

If you want to check whether yours has chances, use an empty /boot/config.txt file and add hdmi_safe=1 to it.

While this won't give you the best resolution, it probably will get you to the login prompt.

After that you can start with tweaking it further until you get the most out of your monitor capabilities.

You can get some useful information about your monitor by entering these 3 commands:

/opt/vc/bin/tvservice -m CEA /opt/vc/bin/tvservice -m DMT /opt/vc/bin/tvservice -s

Use the Raspberry Pi Video Modes reference link to yield the above results and finetune.

After rebooting the Pi, your monitor firmware might show errors like 'out of sync' or 'resolution not supported'. Lower the resolution and/or refresh rate and try again.

After testing I got good results even with small Chinese $3 adaptors connected to the cheapest monitors available in the shop. Out of the box the converter gave a blank screen with the monitor going into powersave mode seconds after. After following the above steps my /boot/config.txt now shows:

hdmi_group=1 hdmi_mode=16

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-5

No +5v supply from setop box like tatasky dishtv hd box in hdmi output so converter not work. it can work properly after supply +5v in pin no.2of hdmi port.

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    Can you expand on this answer please? I don't understand what you're trying to say.
    – Jacobm001
    Commented Jun 9, 2015 at 18:54

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