1 Topic by electro_pagoda

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Topic: 15Khz output from VGA port and >31Khz output from DVI/HDMI port

I intend to connect a pc to a CRT television set which has SCART input. I intend to use an UMSA - Ultimate SCART Adapter . It converts 15Khz RGBHV via a DSUB HD 15pin, to 15Khz RGBS SCART signal.
Either that, or a custom-made VGA to SCART cable, from the descriptions of both, they seem to do the exact same thing.

The pc in question has an ATI Sapphire Radeon HD 4670 Series GPU, which has a VGA port, a DVI port and an HDMI port.
Technically, to my understanding, all I need to do is the following:
Make the graphics card output a 15Khz signal (by using ATOM-15, CRT Emudriver, etc )
Connect it to the adapter via VGA cable, then connect the adapter to the CRT tv via SCART cable. (or just use the custom cable)

However, I would also like to connect a relatively new flatscreen LCD pc monitor to said pc via the DVI port. That way I would have a pc connected to both a CRT tv (for old games, shows, etc ) and a LCD monitor (for document editing, newer shows and games, etc ) using the same graphics card. That would be my ideal setup. I don't think I've seen a single thread that has to do with connecting an LCD pc monitor and a CRT tv to the same graphics card, so I'm posting this here.
From what I have read, I understand that most LCD pc monitors need a default 31Khz signal, or higher, from the graphics card, while most CRT tvs need a strict 15Khz signal.

I would like to ask:
Can I make it so that the graphics card would output a 15Khz signal from its VGA port, and output a 31Khz signal or higher (the way it has always done before being modified) from its DVI port? (or vice-versa: 15Khz from DVI and >31Khz from VGA)

In short, can a single graphics card support multiple signal frequencies?

Does any of the software featured here allow such a function? (If not, I'll just use a separate pc for crt stuff.)
Is the graphics card's HDMI output affected by said software as well?
Is ATI Sapphire Radeon HD 4670 supported by said software?
Will all of that run on win7 64bit?

2 Reply by Calamity

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Re: 15Khz output from VGA port and >31Khz output from DVI/HDMI port

electro_pagoda wrote:

I intend to connect a pc to a CRT television set which has SCART input. I intend to use an
In short, can a single graphics card support multiple signal frequencies?

The answer is yes (that's a frequently asked question).

The idea is simple: you can add custom video modes to your card, each of them at any random frequency. All these modes will be available for you to choose at any time. It's up to you to configure each connector to use any or those modes (VGA->15 kHz, HDMI->31-or-whatever kHz, etc.)

Your HD 4xxx is supported and will run on W7-64 bits.

3 Reply by electro_pagoda

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Re: 15Khz output from VGA port and >31Khz output from DVI/HDMI port

Thanks for the reply!
I phrased my question badly, I'm sorry.
I meant:
Can I simultaneously use an old CRT television and a new regular LCD monitor? As in: having them both connected to the computer at the same time, as "dual monitors", and having the desktop extending on both the CRT and the LCD.

And for instance, having the CRT tv display 640x480 at 15Khz and the LCD monitor display 1600×900 at 31Khz+, at the same time, both plugged into the same video card (CRT being plugged into the VGA port and LCD being plugged into the DVI port), desktop extending on both of them.

4 Reply by Calamity

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Re: 15Khz output from VGA port and >31Khz output from DVI/HDMI port

Yes, it is possible. It was implied in my reply by the way.

5 Reply by electro_pagoda

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Re: 15Khz output from VGA port and >31Khz output from DVI/HDMI port

Thanks a lot, and sorry for the spam!

6 Reply by Calamity

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Re: 15Khz output from VGA port and >31Khz output from DVI/HDMI port

You're welcome. Tell us how it goes.