AOC U2868PQU 4K unusable flickering

FordneyMcCumber · 16 Jun 2014 at 16:29

Hi

I just received my AOC U2868PQU from overclockers.co.uk and when I try to set my refresh rate to 60Hz I get very bad flickering and have to go back to 30hz.
The whole reason for buying this monitor is for the 60hz so the fact it doesn't work at all is most annoying!
I am using an R9 290 (also from overclockers) and the DP cable that came with it I am also using the latest AMD beta drivers on Win 8.1.
Does anybody know how to fix this as I may decide to simply return it and go back to 1080p as there is no point at all having 4k 30hz!

Thanks in advance.

FordneyMcCumber · 16 Jun 2014 at 16:42

Well I thought AMD had sorted out their driver problems years ago maybe not then.
If it's not fixed before the return date then I will return it, but hopefully by then AMD will have got their act together. I waited to by a 4K monitor for this reason but I suppose I must learn my lesson not to buy AMD if I want good support and drivers.
Anyway is there a way to easily find out when this issue has been addressed?

FordneyMcCumber · 16 Jun 2014 at 17:00

I'll watch and hopefully soon AMD will be able to fix this.

FordneyMcCumber · 16 Jun 2014 at 17:22

The problem is that nvidia has no such problem!

FordneyMcCumber · 16 Jun 2014 at 18:55

I imagine the update will be out in the next beta driver there hasn't been one of those since may 23 so hopefully it will be soon.
If I was the one selling these monitors I would not be pleased about this at all I hope overclockers is getting on to AMD about this or soon they will have two of these returned!

FordneyMcCumber · 18 Jun 2014 at 09:11

I have done further testing and the problem is not with AMD's drivers.
I know this because at the boot screen it outputs the full resolution of 3840x2160 at 60hz and there is flickering still.
This must mean that there is an incompatibility in the firmware of the monitor or the Graphics Card.
This means NO DRIVER UPDATE from AMD can fix this.
I will try bios updates on the card but if that doesn't work I will definitely return asap.
I advise other people with the problem to return the monitor because other than bios updates for the gpu I can see no way that this can be fixed!

FordneyMcCumber · 18 Jun 2014 at 09:15

How do I go about requesting the return of this monitor there is not a webnotes option for return!!!

FordneyMcCumber · 18 Jun 2014 at 09:20

no if it was it wouldn't be outputting at 60hz

less of the hostility please!

FordneyMcCumber · 18 Jun 2014 at 09:24

Do I just us the webnote RMA

FordneyMcCumber · 18 Jun 2014 at 09:40

If you care to read the first post you would know what I was using the included DP 1.2 cable and that 60hz 4k does work 100% but with massive flickering and that is the problem and is why I will probably send back.

FordneyMcCumber · 18 Jun 2014 at 10:24

Have tried to flash updated bios has no effect so will be RMAing today

FordneyMcCumber · 18 Jun 2014 at 11:01

Marine-RX179 said:
Could it be just the simple case of faulty cable?

I wish it was but it works at 30hz and every other resolution, its the one that came in the box and I don't own another DP cable so I can't test it. Surely overclockers didn't put a DP 1.1 cable in with it?

FordneyMcCumber · 18 Jun 2014 at 12:13

Is RMA the wrong thing as I didn't see any option to write to them about DSR??
If it is my card then there is nothing I can do as I got it last year and probably can't RMA etc.
If driver updates fixed it I would be surprised as it happens when no drivers are loaded and 3840x2160 60hz is output in boot screens etc.
I reckon that this is a problem caused by an incompatibility between the AOC U2868PQU and my R9 290 who is responsible I don't know but as it is said that it works on Nvidia it is probably AMDs problem. I am not going to wait for drivers as if they don't ever fix it then I will not be able to DSR and will have to buy a Nvidia card to fully use this monitor and I'm not willing to do that.

FordneyMcCumber · 18 Jun 2014 at 13:46

Custom resolutions are only possible in nvidia control panel not on amd ccc

I have decided not to go ahead with return as after looking into it further the issue is caused by the way that the r9 290 outputs over DP, if AMD can fix it I would be surprised as it appears to be caused by the signal coming from the display-port cable being to weak and dropping out it also affects all the other 4k monitors like the asus and samsung. i am going to buy a very short DP cable as this is said to fix the problem?

FordneyMcCumber · 18 Jun 2014 at 19:57

I have done more research and problem is that the DP signal on AMD cards is too weak if crappy cables (like the one included) are used and this causes the signal to drop out. Nvidia does not have this problem because DP 1.2 tech works properly in their cards. Some on other forums report that buying decent cables with less signal loss or shorter cables fixes the problem. That's what I am trying next. Custom resolutions are a non-fix anyway as if its less than 60hz it's not working properly and I doubt the monitor would except random resolutions anyway.

FordneyMcCumber · 18 Jun 2014 at 20:51

I have a ordered the shortest possible cable(to reduce loss) from amazon and hopefully when it arrives the loss will be low enough for it to work I will report back on the result.

FordneyMcCumber · 18 Jun 2014 at 23:45

I guess MST mode is different but from what I have read (no absolute link) people have had the exact same setup and cable and had problems with r9 290 and not with Nvidia.
I have seen a post saying that the 295X2 did not have any problems and in the same topic people posting problems with r9 290/r9 290X.

I don't believe this: https://twitter.com/Thracks/status/478145362415194112

FordneyMcCumber · 19 Jun 2014 at 20:04

The research that I have done suggests that the signal from the card may be too weak and that causes the drop out. I have purchased a new DP cable that is of better quality and half the length of the included one this should reduce signal loss and therefore may fix the problem. It doesn't look good because despite AMD claiming it's not hardware it is because the issue still exists when no drivers of any kind are loaded. Still AMD could push a driver that fixes it in windows. In the meantime I am looking for a workaround and if I find one I will post it.

FordneyMcCumber · 19 Jun 2014 at 22:24

Not got the new cable it was dispatched today. Also I tried to trick the monitor into giving me 60hz 4k by combining two inputs at 1920x2160 60hz in the picture by picture mode but it turns out it can't handle that and if it detects you doing that it disables the mode. If AMD don't have any fix for this and I have a feeling that they won't then soon word will spread and news articles will start coming out about this then they will be sorry!

FordneyMcCumber · 19 Jun 2014 at 22:33

It worked for me but only if they were both 30hz and the image was squashed and very hard to read but it could just be more of those low quality untested drivers from AMD!