5870 and using all 3 ports possible?

[sboerup]

Sorry if this is a repost, a quick search and I didn't find anything.

The new 5770 and 5870 have 2 mini-displayports and 1 DVI. I read somewhere on Apple's site that you can only use 2 of them, but most of the PC available cards you can easily use all 3.

I have 2x20" LCDs and 1x30". I'm currently running the 2600XT and 4870 in my 2008 MP. But when my 2010 MP arrives, do I need to get another card, or can I run all 3 displays (with appropriate adapters) on a single 5870?

[Cindori]

you will be able to run 3 displays, but not eyefinity

[Chupa Chupa]

Yes, it supports 3 monitors up to 2560x1600.

[chrisS]

Do all 3 monitors have DVI connections or are some MiniPort ?

If all 3 are DVI, my understanding is you'll need one Dual Link DVI adapter ($99) and a plain DVI Adapter ($29).

Is that correct ?

[sboerup]

Thanks for the confirmation . . . I was just reading over the "features" section on the Apple page and it did mention being able to power 6 displays, so I figured I must have read the "only 2 displays at a time" for the 5870 somewhere else.

[sboerup]

Do all 3 monitors have DVI connections or are some MiniPort ?

If all 3 are DVI, my understanding is you'll need one Dual Link DVI adapter ($99) and a plain DVI Adapter ($29).

Is that correct ?

I'll run my 30" on the DVI, and the 2x20"s i'll just run with a Minidisplay cable to DVI from Monoprice for $9.

[darwin022]

Yes, it will work. Depending on the monitors/resolutions you're using, you'll probably have to get an "active" Displayport -> DVI adapter (the $100 apple one or a $100 one from Amazon. Either way, $100 more each monitor. ugh.

[skiffx]

Yes, it will work. Depending on the monitors/resolutions you're using, you'll probably have to get an "active" Displayport -> DVI adapter (the $100 apple one or a $100 one from Amazon. Either way, $100 more each monitor. ugh.

why cant you just use minidisplay to dvi ?

[chrisS]

http://forums.macrumors.com/showthread.php?t=986174

[skiffx]

http://forums.macrumors.com/showthread.php?t=986174

So if I want to drive 4 dvi monitors, from 2 cards, 5870 and gt120, those minidisplay > dvi adapters for $10 will do fine, but if Ill want to connect another monitor or a tv I would need to get the active one right?

[J the Ninja]

So if I want to drive 4 dvi monitors, from 2 cards, 5870 and gt120, those minidisplay > dvi adapters for $10 will do fine, but if Ill want to connect another monitor or a tv I would need to get the active one right?
The shortest summary I can give is: If you want to use all 3 outputs on one card, one of the displays MUST be either native DP, or use an active converter of some kind.

Come up with any combination you like, that rule still stands. It's hardware limitation of the 5000 series. Something about how DVI/HDMI requires a separate clock signal for each display, but DP doesn't, and the card can only generate 2 clock signals, IIRC.

[skiffx]

The shortest summary I can give is: If you want to use all 3 outputs on one card, one of the displays MUST be either native DP, or use an active converter of some kind.

Come up with any combination you like, that rule still stands. It's hardware limitation of the 5000 series. Something about how DVI/HDMI requires a separate clock signal for each display, but DP doesn't, and the card can only generate 2 clock signals, IIRC.

Thats interesting, I just got off the phone with an apple 'engineer', he told me that you can drive all three dvi monitors, provided 2 of them will have the MD > DVI adapter, and that Apple does not even offer any active adapters and he didnt know what they were.

He also told me that my other plan to stick a gt120 along side 5870 to drive the 4th monitor is not going to work due to the fact that the PSU wont be able to power it up.

He is either an 'engineer' indeed or maybe he knows something about these particular Apple 5870s.

[J the Ninja]

Thats interesting, I just got off the phone with an apple 'engineer', he told me that you can drive all three dvi monitors, provided 2 of them will have the MD > DVI adapter, and that Apple does not even offer any active adapters and he didnt know what they were.

He also told me that my other plan to stick a gt120 along side 5870 to drive the 4th monitor is not going to work due to the fact that the PSU wont be able to power it up.

He is either an 'engineer' indeed or maybe he knows something about these particular Apple 5870s.

Apple's MDP-Dual-link adapter IS an active converter. (When going to a 2560x1600/1440 DVI display from DisplayPort, you have to use an active converter, because DP doesn't support passive conversion to dual-link, it only carries a single link signal. And that res requires dual link)

Unless Apple conjured up special 5870s with a 3rd clock generator, you are not getting 3 DVI displays off that card without an active converter.

[skiffx]

Apple's MDP-Dual-link adapter IS an active converter. (When going to a 2560x1600/1440 DVI display from DisplayPort, you have to use an active converter, because DP doesn't support passive conversion to dual-link, it only carries a single link signal. And that res requires dual link)

Unless Apple conjured up special 5870s with a 3rd clock generator, you are not getting 3 DVI displays off that card without an active converter.

So Apple's MDP>DVI for 30$ is essentially the same as the 100$ active one from newegg, as mentioned by others above?! Or more likely its just and overpriced 10$ like the previously mentioned monoprice one. (http://www.monoprice.com/products/product.asp?c_id=102&cp_id=10246&cs_id=1024604&p_id=5999&seq=1&format=2)

[J the Ninja]

So Apple's MDP>DVI for 30$ is essentially the same as the 100$ active one from newegg, as mentioned by others above?! Or more likely its just and overpriced 10$ like the previously mentioned monoprice one. (http://www.monoprice.com/products/product.asp?c_id=102&cp_id=10246&cs_id=1024604&p_id=5999&seq=1&format=2)

No!

The $30 Apple one is passive, the active one from Apple is also $100.

[skiffx]

No!

The $30 Apple one is passive, the active one from Apple is also $100.

Gotcha, thanks :)