Dreamcast VGA confusion

Dominance9

Pleasure Goal
Joined
Dec 12, 2015
Posts
146
Need some help with some dreamcast vga confusion Im currently having. I have a older sony trinitron crt that I play all my older games on. It has a DVI port on the back. So my first thought was I am going to buy a DVI to VGA converter for it and pick up a VGA cable for my dreamcast. Except when I hooked it up I didnt get any video just sound.

Any thoughts as to why it isnt working?

Whats the difference between a dreamcast VGA box vs. just the VGA cable?

Thanks for any input
 

GohanX

Hollywood Hulk Gohan
Joined
Sep 28, 2001
Posts
11,676
VGA is analog, dvi can pass either an analog or digital signal, I would guess that the tv is only looking for a digital signal.



What is the model number of the monitor?
 

Speed3

Marked Wolf
Joined
Jul 7, 2015
Posts
215

Nice vid on DC VGA, I'm pretty sure that VGA doesn't carry audio signal you'd need to plug into your TVs 3.5 headphone jack most TVs have one right next to the VGA in.
 

DecepticonZero

Lucky Glauber's #1 Fan
Joined
Mar 8, 2006
Posts
4,647
You shouldn't need any "converter". A simple vga to dvi passive adapter should be fine. As they said above, the port must be dvi-a compatible for it to work, which I'm pretty sure that model Trinitron is.
 

Tech&Music

Another Striker
Joined
May 14, 2016
Posts
325
It won't work. I first looked at the specs where Sony called the DVI port "DVI-HDTV". That already raised my suspicions of it being a DVI-D port (DVI-D is digital only, DVI-I is digital and analog), and looking in the manual confirmed this. Specifically these two things:

DVI.JPG

This DVI port lacks contacts above the little spade pin. That means it's an DVI-D connector, which means it can't accept any analog video.
As you can see, it's a DVI-D connector:

DVI-D.jpg

But not only that, the manual goes on to say this about the DVI port:

DVI2.JPG

Not only can it not accept any analog video, it can also only accept DRM video sources, so even a computer's DVI as said wouldn't work. So sorry, but the Dreamcast's VGA isn't going to work over this DVI port.
 
Last edited:

Dominance9

Pleasure Goal
Joined
Dec 12, 2015
Posts
146
Thanks for the replies. I had no idea only certain games were vga. So by the sounds of it VGA aint happening on that monitor huh? That sucks. But at least I know now. Right now Im just running a S-video cable and it looks good but Im always curious if something else would look better.

2 side questions I have though if anyone knows:

Whats the point of a Dreamcast VGA box over just a Dreamcast VGA Cable. I have a VGA box from a system I picked up years ago and it outputs S-Video, VGA and composite. Is there any advantage with that box over just the normal S-video or vga cables?

Would my monitor take a HDMI input if I bought a DVI to HDMI adapter / cable and wanted to run a Retron 5 HDMI to it?
 

Tech&Music

Another Striker
Joined
May 14, 2016
Posts
325
It could take a HDMI signal, as DVI-D and HDMI are both just TMDS, but I don't think the Retron 5 has HDCP copy-protection on its HDMI signal which is required by the TV.
 

grimmythereaper

Quiz Detective
Joined
Jun 7, 2016
Posts
84
what vga cable are you using? i have one that feels like its in all the way when its only in the dreamcast port about halfway
 

Dominance9

Pleasure Goal
Joined
Dec 12, 2015
Posts
146
It could take a HDMI signal, as DVI-D and HDMI are both just TMDS, but I don't think the Retron 5 has HDCP copy-protection on its HDMI signal which is required by the TV.

Thats too bad. That was kinda the only reason I wanted a retron 5. Thanks for the info though!
 

WNivek

Overtop Pathfinder
Joined
Apr 5, 2016
Posts
104
It could take a HDMI signal, as DVI-D and HDMI are both just TMDS, but I don't think the Retron 5 has HDCP copy-protection on its HDMI signal which is required by the TV.

I could be wrong, but I was under the impression that HDCP is only ever a problem if the video device wants to use it but the display doesn't support it; not the other way around.
 

Kid Panda

The Chinese Kid
Joined
Jun 13, 2010
Posts
12,507
If I'm not mistaken some games could use the VGA cable but couldn't use the VGA box and vice versa. VGA cable was an early release thing though and they dropped it right quickly.
 

Xian Xi

JammaNationX,
Joined
Dec 1, 2005
Posts
27,694
Are you using a DVI to VGA converter or VGA to DVI Converter, they both exist but you would need the latter.
 

mjmjr25

Critical Damage!,
Joined
Dec 18, 2010
Posts
2,622
I think the value of the "VGA BOX" as opposed to a straight VGA cable was the convenience of having VGA / S-VID / Composite / Stereo Out all in one cable - so if it were a game that didn't play in VGA, you just had to change the input on your TV and not change your AV cable.
 

GohanX

Hollywood Hulk Gohan
Joined
Sep 28, 2001
Posts
11,676
Yeah, and some vga boxes like Beharius's have some extra features, but for strictly vga a regular cable will work fine if it's made of good components.
 

DanAdamKOF

Iori's Flame
Joined
Jun 15, 2002
Posts
8,245
You can encode VGA to YPbPr and your TV will treat it as 480p. I think there's some caveats with DC's aspect ratio with VGA out but it's a start.
 

Tech&Music

Another Striker
Joined
May 14, 2016
Posts
325
I could be wrong, but I was under the impression that HDCP is only ever a problem if the video device wants to use it but the display doesn't support it; not the other way around.
I dunno, I'm just going by what Sony wrote down in the manual, which is kind of vague. They make it seem like HDCP is required.
 

Dominance9

Pleasure Goal
Joined
Dec 12, 2015
Posts
146
Hmm, so retron 5 might work then?

For the DC I was just using a straight VGA cable to a VGA to DVI adapter. Not a convertor only a $5 adapter. To get it to work with my monitor I'll need something like in the ebay link you posted?
 

Xian Xi

JammaNationX,
Joined
Dec 1, 2005
Posts
27,694
Hmm, so retron 5 might work then?

For the DC I was just using a straight VGA cable to a VGA to DVI adapter. Not a convertor only a $5 adapter. To get it to work with my monitor I'll need something like in the ebay link you posted?

If you want it to work the way you want it to using that Sony TV on that DVI port.
 

ResO

Chang's Combo Meal #6
20 Year Member
Joined
Jan 8, 2001
Posts
8,000
If you want it to work the way you want it to using that Sony TV on that DVI port.

I think the cheapest route would be to get a VGA to HDMI converter for like $10 on eBay and use an Hdmi to Dvi cord/adaptor.
 
Top