7950 and Dual Link DVI

spoffle · 5 Jul 2012 at 17:44

I'm going to be upgrading, or rather building a new PC in a few months and I'm going for 2 7950s, but are there any 7950s that have 2 dual link DVI ports on them? It seems like most AMD cards now only have 1 dual link port. I've got 3x 27" monitors that need a dual link input and would prefer to use only 1 active DP adapter.

Thanks!

pgi947 · 5 Jul 2012 at 17:54

From what I can see, most if not all appear to have 1 x DL-DVI, 1 x HDMI & 2 x MDP.

Take it you have 3 x 120hz screens?

spoffle · 5 Jul 2012 at 18:02

2560x1440 screens. I've got them running on a 6950 now, and the active DP adapters are a bit of a pain, they seem quite temperamental, so would prefer to be able to run 2 on straight DVI signals.

pgi947 · 5 Jul 2012 at 18:43

I've just re-read your first post.

If getting two 7950's and want to use only the one active adaptor then surely use the DL-DVI on each card and then the MDP on another?

Or even give a pair of 670's a try, the windforce comes with dual DL-DVI ports, giving you 4 in total over 2 cards.

Steveocee · 5 Jul 2012 at 18:45

pgi947 said:
I've just re-read your first post.

If getting two 7950's and want to use only the one active adaptor then surely use the DL-DVI on each card and then the MDP on another?

Or even give a pair of 670's a try, the windforce comes with dual DL-DVI ports, giving you 4 in total over 2 cards.

Didn't think you could do that with x-fire? I thought only 1 card's ports were active?

pgi947 · 5 Jul 2012 at 18:51

Steveocee said:
Didn't think you could do that with x-fire? I thought only 1 card's ports were active?

Not sure at all tbh, never ran multi-monitors from an AMD card, was just a stab in the dark that all display outputs would be active. If this is not the case then I apologise

spoffle · 5 Jul 2012 at 19:01

pgi947 said:
I've just re-read your first post.

If getting two 7950's and want to use only the one active adaptor then surely use the DL-DVI on each card and then the MDP on another?

Or even give a pair of 670's a try, the windforce comes with dual DL-DVI ports, giving you 4 in total over 2 cards.

There's quite a big price difference between Windforce 670s and the 7950s I'm looking at, it's getting close to £150 difference! Plus the 7950s have 3GB of RAM which is going to be much more suitable for eyefinity on these monitors.

As far as I know, you still can't use the display outputs on the secondary card with AMD cards, which is a bit **** really.

pgi947 · 5 Jul 2012 at 19:11

spoffle said:
As far as I know, you still can't use the display outputs on the secondary card with AMD cards, which is a bit **** really.

That sucks, its looking like your only option is another active adaptor unfortunately

Either that or trade your monitors in for something with onboard DP.

spoffle · 5 Jul 2012 at 19:32

pgi947 said:
That sucks, its looking like your only option is another active adaptor unfortunately

Either that or trade your monitors in for something with onboard DP.

I've already got 2 active DP adapters, just sometimes they throw a tantrum and need to be unpluged and plugged back in. It's not really much of a problem, just convenience. I would have prefered onboard DP of course, but I got my monitors for less than £200 apiece so there's nothing to I could trade to of the same price that isn't a variation on what I've got.

theCrim · 5 Jul 2012 at 19:55

In crossfire you have to use the ports on your first card. The ports on the other card aren't active. What inputs do your monitors have?

spoffle · 5 Jul 2012 at 20:01

theCrim said:
In crossfire you have to use the ports on your first card. The ports on the other card aren't active. What inputs do your monitors have?

Yeah, I don't get why they haven't done something about that.

Each monitor has 1 dual link DVI port and that's it. I came from 3x 24" dells that had a whole host of ports, so I didn't need to use any adapters for them.

theCrim · 5 Jul 2012 at 20:13

If you get a 7950 with a dl dvi-d port and a couple mdp/dp ports depending on your 2 active adapters then you're good to go.

pgi947 · 5 Jul 2012 at 20:35

theCrim said:
If you get a 7950 with a dl dvi-d port and a couple mdp/dp ports depending on your 2 active adapters then you're good to go.

He has the same issue with the active adaptors and MDP that I had though crim, it throws a tantrum and needs to be unplugged. I can 100% see why he wants to avoid using them.

@spoffle, whats the budget for the two cards? may also be worth seeing what revision of HDMI is on the 7950, don't some of the newer revisions of HDMI allow high resolution/high refresh rate?

theCrim · 5 Jul 2012 at 20:51

Yer I know but I said what I said because it's a compromise for wanting to use with monitors with only DL-DVI-D ports in his case.

You either spend 2 x £70-£125 on each of the two active adapters(which he's already done I'm guessing) to run 2 of the 3 DL-DVI-D monitors and then run the 3rd off the only DL-DVI-D port your card has. He mentioned his monitors were 27" for under £200 ea so unless these are Catleaps or he managed to get a really good deal on some good quality 27" monitors then he may as well bin the cheap monitors and go with 27" monitors with dp ports and grab himself a couple mdp > dp cables.

Not sure if this makes sense, makes sense in my lil head though :cool:

spoffle · 5 Jul 2012 at 20:51

pgi947 said:
He has the same issue with the active adaptors and MDP that I had though crim, it throws a tantrum and needs to be unplugged. I can 100% see why he wants to avoid using them.

@spoffle, whats the budget for the two cards? may also be worth seeing what revision of HDMI is on the 7950, don't some of the newer revisions of HDMI allow high resolution/high refresh rate?

Oh, yeah I completely forgot about that. I remember reading that some 7 series cards can do 4k from the HDMI port. I'm generally looking for the cheapest 7950s I can get really, which is just over £500 at the moment. By the time I end up getting them they could well have dropped in price though as it's a few months away yet (November).

theCrim said:
Yer I know but I said what I said because it's a compromise for wanting to use with monitors with only DL-DVI-D ports in his case.

You either spend 2 x £70-£125 on each of the two active adapters(which he's already done I'm guessing) to run 2 of the 3 DL-DVI-D monitors and then run the 3rd off the only DL-DVI-D port your card has. He mentioned his monitors were 27" for under £200 ea so unless these are Catleaps or he managed to get a really good deal on some good quality 27" monitors then he may as well bin the cheap monitors and go with 27" monitors with dp ports and grab himself a couple mdp > dp cables.

Not sure if this makes sense, makes sense in my lil head though

I've already got the adapters (some how I managed to get them for £15 each) they generally work fine for the most part. They will occasionally throw a hissy fit at random but most of the time it's when the computer goes in to sleep mode or the monitors go in to standby, the one connected to the DVI port directly comes back on fine, the two connected to the adapters either don't come back on without replugging the adapter or the screens are garbled like a rubbish analogue signal.

The monitors aren't Catleaps, they are however similar, they're from another Korean manufacturer and they use the same panels. They look identical to the 27" Hazros.

What I'm asking though is about a future card I want to get, as I would have expected some changes to have been made with the 7 series when it comes to outputs when compared to the 6 series.

theCrim · 5 Jul 2012 at 21:16

O right I just read yours were running 60hz nvm then.

Are they the new Panatlion ones?

Is your setup for gaming or photo editing?

Well not even the the up and coming ROG MATRIX HD 7970 has 2 dl dvi ports. So I don't know how far into the future a card with 2 dl dvi ports will be released.

spoffle · 5 Jul 2012 at 21:21

They're Acheiva Shimians. As pgi947 pointed out, the new cards do have HDMI 1.4 outputs, so I'm trying to find some info on people using 2560x1440 monitors on HDMI 1.4.

I'm using them for a bit of everything really, games, CAD, photoshop and a bit of website work.

Edit: According to here: http://www.amd.com/uk/products/desktop/graphics/7000/7950/Pages/radeon-7950.aspx#3

HDMI® (With 4K, 3D, Deep Color and x.v.Color™)

Max resolution: 4096x3112
1080p60 Stereoscopic 3D
Quad HD/4k video support

Which looks like it *should* support 2560x1440 at 60hz, but I can't find any examples of anyone using it themselves.

pgi947 · 5 Jul 2012 at 21:36

Grab an HDMI > DL-DVI cable and find out? iirc they are pretty cheap.

I can't say for certain but in some cases doesn't using a DVI 1>2 y-cable convince the machine it is outputting to two separate displays from one output?

spoffle · 6 Jul 2012 at 00:59

Looks like I'll have to wait until I buy them to find out. Thanks for all the suggestions.

Steveocee · 6 Jul 2012 at 08:11

DO the monitors ONLY have DL-DVI inputs?
Stupid question I know but do they not have DP inputs aswell?