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post #1 of 18 Old 01-29-2008, 11:29 AM - Thread Starter
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Hi,

One quick question, is RGB the same as VGA?! My TV (Sonly KLV-32s200a), has a RGB port at the back, and the TV manual talks about VGA stuff (under the PC Input Signal Reference Chart), stating something like the following

Signals Horizontal (Pixel) Vertical (Pixel) Horiz Freq (kHz) Vert Freq (Hz)
XVGA 1360 768 47.7 60

Does this mean, I can use the standard DVI to VGA cable provided with the Mac Mini and use that? or do I have to go the HDMI route?

Thanks,
Jatin
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post #2 of 18 Old 01-29-2008, 11:51 AM
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Yes VGA carries RGBHV--RGB and Horizontal and Vertical Sync information along with DDC info where available.

Now is that port on your TV a d-sub 15 pin standard VGA connector?
http://en.wikipedia.org/wiki/VGA_connector

If it is, then yeah you should be able to output VGA from a PC to the TV with a proper cable.

However if the TV has DVI or HDMI connections on it, it's better for you to connect it that way. DVI/HDMI is a digital signal and if it's a digital-based display tech TV, then you're better off using that. Also if the TV does resolution above 1360x768 (i.e. if it does 1080p) you can get higher resolution by going via DVI/HDMI...
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post #3 of 18 Old 01-29-2008, 11:57 AM - Thread Starter
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Well yeah I believe that is the connector on the back, as far as I know, the TV does 1080i and 720p. Here's a link to the pdf manual

http://www.sony.co.in/support/manual...ite=hp_en_IN_i

Would I do a DVI to HDMI conversion or should I just stick to VGA?

Thanks!
Jatin
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post #4 of 18 Old 01-29-2008, 12:00 PM
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Quote:
Originally Posted by jatin4882 View Post

One quick question, is RGB the same as VGA?!

Generally, no. Usually RGB means some type of RGB analog waveform stream over wire with BNC connectors.
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Originally Posted by jatin4882 View Post

Does this mean, I can use the standard DVI to VGA cable provided with the Mac Mini and use that?

If it's possible it would be mac mini --> dvi out --> converter to vga --> vga cable --> tv vga (rgb) input. your manual says that RGB is 15 pin VGA. Sometimes this is called DB15.
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or do I have to go the HDMI route?

if your mac mini has hdmi out that might be better pq, but I have no idea how the mac mini is designed. if you wanted us to give you precise info about the best way to hook up your mini to your tv we would need the model number. with apple it's m/la_____ or something like that.
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Would I do a DVI to HDMI conversion or should I just stick to VGA?

That would probably give you better pq since your vga input is a waveform signal and can degrade over distance. DVI to HDMI would be all digital signal. I have no experience with dvi to hdmi and your specific mac mini computer. I would say try it out. If I had to guess I would say it'll probably work.
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post #5 of 18 Old 01-29-2008, 12:05 PM - Thread Starter
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hey!

thanks! so that would mean that a straight DVI to VGA will not work! I haven't bought a Mac Mini yet, but I'm just scouting around before I do that. Here's the layout of the Mini

http://www.asia.apple.com/macmini/specs.html

and that would mean that the best thing would be to get a DVI to HDMI cable, and just hook that into the TV.

What do you think?
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post #6 of 18 Old 01-29-2008, 12:08 PM
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Quote:
Originally Posted by jatin4882 View Post

Well yeah I believe that is the connector on the back, as far as I know, the TV does 1080i and 720p. Here's a link to the pdf manual

http://www.sony.co.in/support/manual...ite=hp_en_IN_i

Would I do a DVI to HDMI conversion or should I just stick to VGA?

Thanks!
Jatin

If your Sony is anything like my 50" SXRD in regards to the PC input, the PC input is pretty much useless. It's limited in resolution and it makes a border around the display if I'm not mistaken. I wouldn't use it--even using a component input would be better (though I doubt your mac has component out). Your best bet is to use HDMI, IMO. You simply need a cable with a DVI connection on one end and an HDMI on the other; OR, a cable with two DVI-D ends and a DVI-HDMI adapter with a made HDMI end; OR, a cable with two HDMI ends and then a DVI-HDMI adapter with an HDMI female end.

If you're buying a new cable, then just buying one a DVI-HDMI cable is easiest, but if you have a DVI or HDMI cable(s) already, you might just need an adapter to make things work.

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hey!

thanks! so that would mean that a straight DVI to VGA will not work! I haven't bought a Mac Mini yet, but I'm just scouting around before I do that. Here's the layout of the Mini

No that's a VGA port alright, it's compatible; but, for the reasons above, it's better not to use it.
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post #7 of 18 Old 01-29-2008, 12:12 PM - Thread Starter
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Hi!

Thank you! I think that makes a lot of sense, and I think the best bet would be to go via the HDMI way.

I was hoping it would be VGA and would work out well...oh well..and then I guess I can play around with the Mac settings and tweak them accordingly.

Thank you soo much for your help!
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post #8 of 18 Old 01-29-2008, 12:19 PM
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Quote:
Originally Posted by jatin4882 View Post

What do you think?

I agree with:
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Originally Posted by ES_Revenge View Post

Your best bet is to use HDMI, IMO.

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Originally Posted by ES_Revenge View Post

It's limited in resolution and it makes a border around the display if I'm not mistaken.

This may be a issue with the way you have the overscan setting configured.
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I was hoping it would be VGA and would work out well...oh well..and then I guess I can play around with the Mac settings and tweak them accordingly.

vga would work. in the apple control panel area under displays there is usually a overscan checkbox you can select to turn on/off the overscan (black border). Sometimes this ends up working out better/worse on different computer/tv combinations in my experience. Page 41 of your manual says your specific tv accepts the tv's native resolution (edit: near native) at 60 cycles/second.

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post #9 of 18 Old 01-29-2008, 12:21 PM - Thread Starter
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Does that mean I should try the stock DVI to VGA cable that comes with the Mini, and if that doesn't work, try the DVI to HDMI cable?
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post #10 of 18 Old 01-29-2008, 12:23 PM
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Originally Posted by jatin4882 View Post

Does that mean I should try the stock DVI to VGA cable that comes with the Mini, and if that doesn't work, try the DVI to HDMI cable?

Well, the converter cable if I'm not mistaken is DVI female to VGA male, and is only about 6 inches long. You would need a extra vga cable, or use one you have lying around to connect the converter cable to your vga tv input.

If you want to spend some extra money for better picture quality then buy a dvi to hdmi cable. The choice is up to you.
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post #11 of 18 Old 01-29-2008, 12:25 PM - Thread Starter
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hmm, HDMI seems the choice I guess! Less tweaking and better quality! Plus I guess it'll be hassle free!

Thank you!
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post #12 of 18 Old 01-29-2008, 12:30 PM
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Thank you!

you're welcome. If you want a decent quality cable I've bought lots of stuff from blue jean cable over the years and would rec. them to you. Here's their dvi to hdmi cables. link. obviously if you wanted something cheaper you could go with monoprice.com. that's about the extent of my dvi to hdmi cable knowledge.
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post #13 of 18 Old 01-29-2008, 12:33 PM
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Well, VGA is RGB, but RGB is not VGA. Red Green Blue is the three analog signals that are transmitting on a variety of different cable.

These include

Component
VGA
Scart

Component carries each signal and then recombines them. VGA sends them, but also send information to the monitor regarding resolution and frequency. Between the two, VGA has twice the amount of bandwidth and can display both a higher resolution and more vibrant colors. Scart is used in Europe.

DVI is a digital connection. Where as VGA is analog. If you send a VGA signal through a digital connection, it will come out as rubbish... unles the display itself is either analog or can convert analog. So what does that mean. It means you can send a VGA signal through a DVI cable and the monitor will accept it if it has a vga input. So you will either need an adapter on the display card or on the monitot (or cable that is one end vga and the other end dvi). What you cannot do is connect a vga port on the card to a dvi only monitor using a cable (unless the card can reprogram that port to be digital)

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post #14 of 18 Old 01-29-2008, 09:39 PM - Thread Starter
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Originally Posted by bjmarchini View Post

Well, VGA is RGB, but RGB is not VGA. Red Green Blue is the three analog signals that are transmitting on a variety of different cable.

These include

Component
VGA
Scart

Component carries each signal and then recombines them. VGA sends them, but also send information to the monitor regarding resolution and frequency. Between the two, VGA has twice the amount of bandwidth and can display both a higher resolution and more vibrant colors. Scart is used in Europe.

DVI is a digital connection. Where as VGA is analog. If you send a VGA signal through a digital connection, it will come out as rubbish... unles the display itself is either analog or can convert analog. So what does that mean. It means you can send a VGA signal through a DVI cable and the monitor will accept it if it has a vga input. So you will either need an adapter on the display card or on the monitot (or cable that is one end vga and the other end dvi). What you cannot do is connect a vga port on the card to a dvi only monitor using a cable (unless the card can reprogram that port to be digital)

that makes sense! so in essence, it just makes sense to stick with DVI to HDMI and plug that HDMI into the TV, and that also takes care of the conversion, since DVI and HDMI are both digital.

I'm just curious (and i dont know if any of you are mac users), but I'm assuming then I'll have to run the so called DisplayConfigX and fix the display to my TV, and I would be setting it to the 1900 x 1080i, since the tv doesnt support 1080p; or as mentioned under WXGA 1360 x 768 with 60hz frequency.

Thanks for your help!
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post #15 of 18 Old 01-30-2008, 11:31 PM
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Quote:
Originally Posted by bjmarchini View Post

Well, VGA is RGB, but RGB is not VGA. Red Green Blue is the three analog signals that are transmitting on a variety of different cable.

These include

Component
VGA
Scart

Right but this is just confusing the issue. You can rest assured the d-sub 15-pin connector on the Sony TV is VGA. It says "RGB" on the label and it is a VGA connector.

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Originally Posted by bjmarchini View Post

Component carries each signal and then recombines them. VGA sends them, but also send information to the monitor regarding resolution and frequency.

Yeah but so does component. Because how else would the TV know to switch different formats? 480i, 480p, 720p, 1080i, and 1080p* are all transmittable via component and you don't have to tell the TV what it's getting, it automatically switches with whatever you send it.

*Note that ATi videocards will only send up to 1080i on component and many TVs, particularly Sonys, only accept up to 1080i on component.

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DVI is a digital connection. Where as VGA is analog. If you send a VGA signal through a digital connection, it will come out as rubbish... unles the display itself is either analog or can convert analog.

You can indeed send VGA over DVI--DVI-I. Look at the right hand side of the connector here:
http://en.wikipedia.org/wiki/Dvi

The DVI standard has a section (the four plus crosskey section) for analog video as well. Analog video obviously can't be sent over the digital section, but there is definitely an analog section to DVI-I. Only DVI-D lacks this part of the connector, as it's all digital and only allows for the TMDS type digital signal. This is, incidentally, how all video cards that have DVI-VGA adapters work--they just use the pins on that side of the connector which are VGA analog video.

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What you cannot do is connect a vga port on the card to a dvi only monitor using a cable

Okay that's true--that would be a DVI-D port on the monitor in that case. But still you're confusing me at this point (and probably the OP even more).

The OP has the following at hand.

A TV that has a VGA input (this is a VGA input on this set) and an HDMI input (and everything below--component, S-Video, composite).

A Mac mini with a DVI-I port. (Well the OP doesn't have it yet but wants to buy one.)

OP wants to know the best way to connect it. Easily this is the HDMI port on the TV by using a DVI-HDMI cable or adapter. That is the best type of connection.

However should they want to use the VGA port they could do that as well. Just put the DVI-I to VGA part onto the port on the Mac and use a VGA cable. However the VGA connection on Sony TVs isn't all that great. In this case it's not that bad because the TV's max input resolution is limited to 1080i and the panel resolution is 1366x768 anyway, which is the maximum resolution the VGA input allows. (Contrast this to 1920x1080 Sony TVs that have the same VGA input which makes it largely useless.) So they could still use VGA fine in this case.

VGA will probably look fine, however HDMI is still technically better since the panel is digital (it's an LCD) and going over VGA requires two conversions. One through the videocard/chipset's DAC and then one at the TV which changes the analog VGA back to digital to display on the TV.

Bottom line is, either is useable but HDMI is the better choice. Since the TV only has one HDMI input from the looks of it, if any other HDMI devices are to be connected, that will probably force the use of the VGA input for the PC unless a switcher is used.
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post #16 of 18 Old 01-31-2008, 07:35 AM
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Right but this is just confusing the issue. You can rest assured the d-sub 15-pin connector on the Sony TV is VGA. It says "RGB" on the label and it is a VGA connector.


Yeah but so does component. Because how else would the TV know to switch different formats? 480i, 480p, 720p, 1080i, and 1080p* are all transmittable via component and you don't have to tell the TV what it's getting, it automatically switches with whatever you send it.

*Note that ATi videocards will only send up to 1080i on component and many TVs, particularly Sonys, only accept up to 1080i on component.


You can indeed send VGA over DVI--DVI-I. Look at the right hand side of the connector here:
http://en.wikipedia.org/wiki/Dvi

The DVI standard has a section (the four plus crosskey section) for analog video as well. Analog video obviously can't be sent over the digital section, but there is definitely an analog section to DVI-I. Only DVI-D lacks this part of the connector, as it's all digital and only allows for the TMDS type digital signal. This is, incidentally, how all video cards that have DVI-VGA adapters work--they just use the pins on that side of the connector which are VGA analog video.


Okay that's true--that would be a DVI-D port on the monitor in that case. But still you're confusing me at this point (and probably the OP even more).

The OP has the following at hand.

A TV that has a VGA input (this is a VGA input on this set) and an HDMI input (and everything below--component, S-Video, composite).

A Mac mini with a DVI-I port. (Well the OP doesn't have it yet but wants to buy one.)

OP wants to know the best way to connect it. Easily this is the HDMI port on the TV by using a DVI-HDMI cable or adapter. That is the best type of connection.

However should they want to use the VGA port they could do that as well. Just put the DVI-I to VGA part onto the port on the Mac and use a VGA cable. However the VGA connection on Sony TVs isn't all that great. In this case it's not that bad because the TV's max input resolution is limited to 1080i and the panel resolution is 1366x768 anyway, which is the maximum resolution the VGA input allows. (Contrast this to 1920x1080 Sony TVs that have the same VGA input which makes it largely useless.) So they could still use VGA fine in this case.

VGA will probably look fine, however HDMI is still technically better since the panel is digital (it's an LCD) and going over VGA requires two conversions. One through the videocard/chipset's DAC and then one at the TV which changes the analog VGA back to digital to display on the TV.

Bottom line is, either is useable but HDMI is the better choice. Since the TV only has one HDMI input from the looks of it, if any other HDMI devices are to be connected, that will probably force the use of the VGA input for the PC unless a switcher is used.

I have actually tested this on my 92" inch screen. DVI/HDMI is far superior. I didn't think it would be, but it is. What I found with double converting a signal is that it tends to create pixels that can"overlap here and there. What I mean by that is this:

Digital images are a series of pixels or dots. With a digital signal, the display is told exactly where to put each pixel and what color it is supposed to be.

With an analog connection, it must map the image onto the pixels and try to figure out how the image will be laid out. A simple image here and there will be fine, but on close inspection there will be some pixels in different locations than on the original.

The best example is a curved line. A digital signal already know where to put each pixel. an analog must map it as best it can. It could be dead on, or it could put a pixel or two our of place along the sides. It can happen in straight lines too.

For the most part, you won't know the difference, but just know that there is a difference.

I think the other difference is color. Just as a digital chip must map where a pixel is located, it must also calculate what color it is. Depending on your displays chipset, this can be where there is the biggest difference.



So use the dvi to hdmi if possible.

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post #17 of 18 Old 03-25-2008, 04:35 AM
 
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I have a Sony 50" SXRD set and I am wanting to connect my MacBook Pro. My laptop has DVI and it comes with a DVI to VGA adaptor cable. My TV has VGA and it also has HDMI inputs. I thought that the best rout would have been to go with a DVI to HDMI cable, but the Sony owner's manual states: "Do not connect a PC to the TV's HDMI input. Use the PC in (RGB IN) input instead when connecting a PC."

Anybody have a Mac and a Sony connected up? If so does it work using the HDMI connection? Have you compared the VGA to the HDMI connection? Thank you.
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post #18 of 18 Old 03-25-2008, 10:49 AM
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There is some misinformation here:
A) "Component" encompases many different kinds of connectors and signals. It just means the video information is separated into parts instead of all in one cable. VGA, SCART, S-video, BNC and YPbPr are component, composite is not.

B) The type of component used on all modern HDTVs, dvd players, etc... is not RGB color space, it is YPbPr with sync on luma.

C) Component YPbPr does carry information about frequency. The information is multiplexed/compressed into the Y component (aka sync on luma).

D) VGA is not usually compatible with BNC (but there are different kinds of BNC). VGA has separate connections for H-sync and V-sync whereas BNC usually has the sync information incoded in the Green color channel (sync on green but not always).

More reading: http://en.wikipedia.org/wiki/Component_video
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