Do I need an active or passive DP->VGA adapter?

[Goi]

Hi,

I have a HP Sandy bridge desktop with intel integrated graphics, and it has VGA and DP output. I have 2 LCD monitors that accept only VGA in. I'm thinking of getting a DP->VGA adapter and connecting the 2nd monitor to the DP to use in a dual display configuration. Will I need an active or a passive adapter?

Thanks.

 

[NoQuarter]

Unlike DP->DVI adapters all DP->VGA adapters are inherently active adapters so any DP->VGA adapter will work.

 

[ErickMaga]

Unlike DP->DVI adapters all DP->VGA adapters are inherently active adapters so any DP->VGA adapter will work.

Can you confirm that to me?

I have a hd6950 and i have 3 vga only monitors, i need 2 miniDP-> VGA adaters. Doesnt matter which kind/brand, whatever? Even from dealextreme.com? Since all dp to vga are active, do you think its going to work, my eyefinity?

It will be like this, dvi-i to vga adater, + 2x miniDP to vga adapter.

Will it work?

thanks!

 

[NoQuarter]

Can you confirm that to me?

I have a hd6950 and i have 3 vga only monitors, i need 2 miniDP-> VGA adaters. Doesnt matter which kind/brand, whatever? Even from dealextreme.com? Since all dp to vga are active, do you think its going to work, my eyefinity?

It will be like this, dvi-i to vga adater, + 2x miniDP to vga adapter.

Will it work?

thanks!

Yes that arrangement would work. Any kind/brand DP->VGA adapter will do the job. I believe most the brands are just rebrands from a single supplier or two so I don't think there's a quality difference between them for the most part. These adapters are inherently a bit flaky though so there's a chance you'll get a dud, so it's better if you can use a 2nd DVI->VGA adapter and only one monitor on DP->VGA if you can arrange that. Plus DVI->VGA adapters are pretty cheap.


If you are curious to the technical reason all DP->VGA adapters are active, DP does not have pass through pins to send an analog signal (VGA) through the connector like DVI does (the 4 pins on their own island in a DVI plug are analog VGA pass through pins). That means to get an analog VGA signal out of a DisplayPort jack, you must take the digital DisplayPort signal and actively convert it into an analog VGA signal.

This differs from DVI because DisplayPort *can* send a DVI signal through the DP jack. This gives you the option of using a passive DP->DVI adapter (which asks the video card to send a DVI signal through the DP jack and just rearranges the pins) or an active DP->DVI adapter (which asks the video card for a DisplayPort signal, then actively converts it to DVI).

Now, current GPUs are only capable of sending a total of 2 VGA/DVI/HDMI signals at once since there are only 2 clock generators on the GPU, but unlimited DP signals. If you are using passive DP->DVI adapters the GPU runs out of DVI signals to send at 2.

If you are using DP->VGA or active DP->DVI converters, which take a native DisplayPort signal and convert it itself, there is no limit - so you need one of these for each monitor past the first 2.

 

[ErickMaga]

NoQuarter tank you very much, i'm feeling a lot better now, monday i'll go and buy 2 DP->Vga adapters and set up my eyefinity finally, you have no idea who i was feeling i was going mad/crazy/sad/desperate. hahahhahaha

You saved me! Thanks a lot!


The passive DVI-> VGA can only be used on the top DVI slot, because the bottom DVI slot is digital only, I tried plugging the passive DVI-> VGA on the bottom DVI slot os all my 3 cards and none of them work, but when i plug me DVI monitor it works.

Thats why i needed 2 DP-> VGA.

Thanks again! I there was a rep+ system, I would give you 10000 reps+

 

[ErickMaga]

Just wanted to let you guys know that it worked.

I got 2 DP->VGA adapters and used with the miniDP->DP that came with the cards.

The adapter i bought was a generic one, which turned out to be a
BizLink KS10031-026

Its not in the amd validated dongle list.
The one there is the BizLink KS10031-131

Thank you all for the help!