On TechReport's frame latency measurement and why gamers should care

Gross.

We have no evidence that AMD was even aware of these other issues before Ryan brought them to their attention. In fact, if you want to assume they were, it paints them in a rather bad light... I prefer to give them the benefit of the doubt. Surely the customer is entitled to know exactly how the product they have paid for is performing...

 

I must admit, now that I re-read the article, it's possible they didn't actually test with frame pacing enabled as I previously had somehow understood the article. If they didn't, my apologies to Ryan.
However, this particular paragraph suggests the tests were in fact done with frame pacing which was clearly mentioned by AMD that it wouldn't work (and despite what it says, I don't understand how anyone could be confused about it since it was clearly mentioned that it's supported only on single display)

 

There seem to have been technical hurdles and tool changes necessary to log the multiscreen issues accurately, which I believe the prior PC Perspective piece indicated.
The author's work, and/or help necessary to set up the new tests has happened to bear fruit right before the next gen announcements.

Given the visual breaks that result from the syncing problem, I believe AMD--or at least its QA department--has been on the same page as you for quite some time.

 

http://techreport.com/blog/25399/here-why-the-crossfire-eyefinity-4k-story-matters

Looks like the AMD defense force are extremely defensive and working overtime to damage control as more and more sites expose AMD's crappy drivers.

 

I liked this quote

*imagines Dave begging

ps: Amd treats a 4k display like a 2 display eyefinity setup In fact 2 monitors arranged horizontally


If they treated it like 2 displays arranged vertically

would the tearing be less noticable (or make no difference) ?

 

Davros, the current 4K panels are actually physically two panels arranged in a 2x1 portait configuration. We do not recommend using HDMI to drive the panels - all our recent products support DP1.2 with multi-stream capabilities and the "Eyfinity" tearing is not present in that mode.

 

Do you mean they are using two 8:9 1920 X 2160 panels combined to one 16:9 3840 X 2160 display?

 

Microstutter
Frame-interleave
4K Bug

Six month later and instead of getting the original frame latency fixed the problems actually tripled now. Who would've expect it huh?

What's next?

 

The problems haven't tripled. Your knowledge has.

 

I'm pretty sure it's hard to glue 2 pieces of glass together, so I assume it's a single physical 3840x2160 panel, but they have duplicate electrical interfaces that each handle half of the panel.

 

The cards may be but are the monitors ???
I found the explaination as to why they are two panels (or possibly 1 panel but electrically its 2 if you know what I mean)

edit: the asus in the quote does have dp why did they not use it does it require a mst hub and they didnt have one ?
fook me they are £100 no wonder, but then again amd cards all have 2 dp outputs

 

To be frank I'm not 100% on the panel situation at the moment, I believe they should all have DP and HDMI inputs if they are targeting 60Hz 40K.

No, the hub is built into the panel. External hubs are required for supporting multiple panels, the 4K panels take a single DP cable input and then split between the internal panels with an internal hub. In other words, why would anyone use two HDMI cables to a single panel when you can use a single DP?

 

Why would a dual-HDMI configuration not work on AMD when it works on NVidia?

 

nv has some sort of lock sync on each scanline

 

How would HDCP work with 2 HDMI?

 

afaik all hdcp content is at a res that is supported by a single hdmi cable

 

Dave how is the Crossfire Eyefinity/4K fix coming up?
I have some 7990s coming my way that need a little sorting out. I read somewhere that we should expect something in november, is that still case or can you comment this in any way?

 

can you crossfire 2x 7990 ?

 

Yes, this bring you to QuadCFX..