eyefinity 3x144hz monitors only getting 60hz

Toggle sidebar Toggle sidebar
O

Octomon

Reputable
Oct 21, 2014
13
0
4,520
Hi all, hoping someone can help here. I have 3xBenQ XL2720Z 27" 144hz monitors, connected to Asus DirectCuII HD7870 in crossfire.
Cable connections are:
Dvi-D to Dvi-D, 2xmini dp to dp
Eyefinity works, crossfire works but i'm stuck at 60hz.

Now after a lot of reading online and some stuffing around I worked out if I only have 1x monitor connected by dvi and the others unplugged, I get 144hz on the dvi connection. I can add the second monitor mini dp to dp and have both running at 144hz.

I can then if I plug in live the 3rd monitor mini dp to dp get all three at 144hz recognized in windows and CC. But as soon as I restart my pc it reverts to 60.

If I try to connect the 3rd screen while off it and then start it up again I get only 60hz in Eyefinity.

Interesting if I disable eyefinity, I can set both the monitors on DP inputs to 144hz, but not the DVI-D connected monitor its stuck at 60hz unless only 2 screens are connected first and the 3rd plugging in live.

It can obviously do it all at 144hz, but to stuff around plugging and unplugging monitors each reboot is a bit much.

So I am wondering if adding an active adapter that supports 144hz would help? but I only have on the card:
1x dvi, hdmi (which I know doesnt support above 60hz so I didnt even bother with that) and 2 mini dp.

so with an active adapter how would I connect it? dvi-d to dvi-d, active mini dp to DVI and a mini dp to DP?

Can anyone confirm if that would work or if there is another way to keep the 144hz setting after a reboot?
 
Sort by date Sort by votes
O

Octomon

Reputable
Oct 21, 2014
13
0
4,520
I am using a Dvi-D dual link cable with crossfire. Are you referring to an Active mini dp to dual link DVI?


If I shutdown and disconnect one of the display port connected monitors i can get both the dvi and dp connected screens set at 144hz, If I connect the 3rd monitor via dp live (shutting down first to connect the 3rd results in the dvi only detecting at 60hz) it will actually set all 3 monitors at 144hz and create and eyefinity group at 144hz. Until restarted anyway.

So I need to know if an active adapter would fix this, since there would still be the same dvi to dvi connection and then 1 mini dp to dp and the new addition being mini dp to dvi instead of mini dp to dp (from what I understand minidp to dp is a native connection on both ends and therefore doesn't require an active adapter, the fact I have this working in eyefinity at 60hz proves this). Frustratingly I know that native Dvi-d to dvi-d and native mini dp to DP both support 144hz.

If there is an "active" adapter that can pump out 1xmini dp to 2xDvi-d outputs at 144hz (as the dp1.2 standard supposedly can support two monitors, but haven't found one yet)

It may well be a limitation of the card, I don't want to spend 50-100 on something unless I am certain that will achieve my goal. Otherwise I am better waiting a while until I can get a better card with more mini display ports on the card.
 
Upvote 0 Downvote
O

Octomon

Reputable
Oct 21, 2014
13
0
4,520


I am currently still just getting 60Hz I believe it is a limitation of the card itself and its outputs, I have read about MST hubs:
http://www.club-3d.com/index.php/products/reader.en/product/mst-hub-1-3.html
Which some ppl claim would do 144hz but on the website itself it says it supports "2560X1600@60Hz" (Curious though if at 1080p higher refresh rates might be available, unconfirmed) at so I was not willing for fork out over $100 for something that may or may not work.

I found this Q&A on newegg:

"josephbra asked: i just got a new Alienware 17 with AMD Radeon™ R9 M290X with 4GB GDDR5. this computer has only one minidp so i want to use this mst hub to out put to 3 Asus VG248QE that has Full HD 1920x1080 and 144Hz rapid refresh rate. so the question is: can i out put to 3 monitors on eyeinfinity full hd at 144 each monitor ? Jun 26, 2014

Jeffrey B: So the way this works out more or less is based on available "bandwidth." Three monitors at 1440p use about 105% of the available bandwidth, so about 10.5 million pixels worth of data available (at 60hz) or 175.5 k at 1hz. Extrapolating for 1080p x3 at 144hz and you end up at about 142% of the available bandwidth. While I haven't tried this, and there may be a caveat about higher hz affects these calculations differently, it wouldn't appear to work."

So still not 100% that it would work.

What I am eventually looking at in my next GPU card is making sure it has 3xmini dp ports on it that supports the refresh rate on 3 monitors. Or unless someone can confirm there is a MST hub capable of support 144hz for each screen.

If I do find another solution I will post back here, but I have searched for ages and not found much useful. I am still hoping to find someone with similar cards that can confirm working using a mst hub or some other kind of adapter.
 
Upvote 0 Downvote
E

evohicks

Reputable
Nov 9, 2014
4
0
4,510
Ok mine is fixed after contacting Mat from AMD, he suggested installing the new 14.11.1 beta driver from AMD website which has a fix for this, now I have all 3 of my monitors running at whatever refresh rate I choose, try them!

 
Upvote 1 Downvote
O

Octomon

Reputable
Oct 21, 2014
13
0
4,520


Wow ok that is exciting news, I can't find the 14.11.1 but I am getting the 14.11.2 beta driver as I type, will see if that fixes it for me too! I am currently on 14.9.




**** UPDATE **** Just finished installing the beta 14.11.2 drivers and it has fixed the issue also, that's awesome thankyou!
 
Upvote 0 Downvote
You must log in or register to reply here.

TRENDING THREADS

Latest posts

Moderators online

Share this page

COMPANY
RESOURCES
FOLLOW
Top Bottom