OLD monitor Dell 29 inch Ultra U2913WM
NEW monitor Dell 27 inch 4K P2715Q
tripplite KVM model B004-DP2UA2-K (2 port displayport 1.2 4k kvm switch)
desktop video card XFX Radeon R9 - 270x
laptop video built in intel
I was already using the kvm to swap the input from a laptop and a dell desktop to a Dell U2913WM monitor without issue.
The desktop PC is having this issue since I swapped the monitor to the P2715Q 4K monitor; the desktop icons all regroup to the upper left corner of the screen when I change the input on the KVM switch. This has also happened with a dell 4K S2817Q but this has never happened on the U2913WM. Everything else works fine on the P2715Q. The laptop is having no issues all icons remain in the same location on the screen.
The desktop is using a Radeon 9 270x and as stated it works fine with the U2913WM at 2850 x 1080 x 60
the desktop is using the 4k monitor at 3840 x 2160 x 60 and the laptop is setup the same but it is running the built in Intel graphics.
the newest drivers are installed on the desktop and the laptop.
I am seeking solution to the icon issue on the desktop PC, I cannot use the entire video desktop to setup icons every time I swap inputs to the monitor ands then swap back to the PC the icons are in the upper left corner.
The issue is not with the montior, but more with the video card driver and the operating system as well as the kvm swtich.
the only thing that has changed from a good working kvm setup has been the monitor. I tried the monitor at different resolutions and it finally holds steady when it runs at 1920 x 1080. the monitor only gets affected when I switch to the other device and back. The OS is windows 10 with the latest patches, the video card has the latest drivers. And the kvm is certified for 4k @60.
Any other ideas?
Exactly which model KVM do you have? Inserting a KVM adds "length" aka delay to the data stream.
This one is limited to HD 2560 x 1600 & USB 3.0 data transfer rates up to 5 Gbps max.
4k @ 60 requires 2 cables per monitor with 1.2
single cable only applies to display port 1.3 and 2.0.
4K@ 30 works because its half the bandwidth.
DisplayPort version 1.3 was approved on 15 September 2014. This standard increases overall transmission bandwidth to 32.4 Gbit/s with the new HBR3 mode featuring 8.1 Gbit/s per lane (up from 5.4 Gbit/s with HBR2 in version 1.2a), for a total data throughput of 25.92 Gbit/s after factoring in 8b/10b encoding overhead. This bandwidth is enough for a 4K UHD display (3840×2160) at 60Hz, a 5K display (5120×2880) at 60 Hz, or an 8K UHD display (7680×4320) at 30 Hz, with 24-bit RGB color. Using Multi-Stream Transport (MST), it can support two 4K UHD (3840×2160) displays at 60 Hz, or up to four WQXGA (2560×1600) displays at 60 Hz in 24-bit RGB mode.
B004-DP2UA2-K triplite latest specs states "Supports video resolutions up to 3840 x 2160 (4K x 2K) @ 60 Hz"
And I am running a single cable to the monitor and it is running at 3840 x 2160 (4K x 2K) @ 60 Hz on the PC and 3840 x 2160 (4K x 2K) @ 30 Hz on the laptop.
Dell 4k monitors come with only 1 display port cable and they work at 4k@60 if the video card supports it.
my verification of the setting being used shows 3840 x 2160 (4K x 2K) @ 60 Hz
This spec may be marketing because they should say Display port 1.3 if they want to make that claim. You also need a video card that supports Mulit Stream transport (MST) It stitches 2 screens to make one 4k image which is not really 4k if ya ask me. 4k 4:4:4 60hz GPU with 10 bit requires quite a fast QUADRO and display port 1.3 minimum. VESA adds that the DisplayPort 1.2 standard is backward-compatible with DisplayPort 1.1a which may be a detection issue crimping the bandwidth as well.
There isn't enough bandwidth for 60hz in 1.2 for 4k 4:4:4 60hz
Kepler based video cards using NVIDIA’s R340 drivers are paired up with very recent 4K TVs, they gain the ability to output to those displays at 4K@60Hz These setups were previously limited to 4K@30Hz due to bandwidth availability, and while those limitations haven’t gone anywhere, TV manufacturers and now NVIDIA have implemented an interesting workaround for these limitations that teeters between clever and awful.
Lacking the available bandwidth to fully support 4K@60Hz the latest crop of 4K monitors have implemented what amounts to a lower image quality mode that allows for a 4K@60Hz signal to fit within the bandwidth limit. To accomplish this, manufacturers are making use of chroma subsampling to reduce the amount of chroma (color) data that needs to be transmitted, thereby freeing up enough bandwidth to increase the image resolution from 1080p to 4K. Defintely not 4:4:4 10 bit.
Specifically, manufacturers are making use of YCbCr 4:2:0 subsampling, a lower quality sampling mode that requires ¼ the color information of regular Y'CbCr 4:4:4 sampling or RGB sampling.
4K is not 4K is not 60hz unless you very uniquely qualify all of the encoding parameters.
please read my details I am running only one monitor. the other monitor was running without issues.
also if you read the review of the KVM product someone has it working fine on a 43 inch 4k monitor.
I am seeing the monitor running at the 4k@60
I want a solution not a specs definition.
The KVM is not supported and not Dell hardware. The video card is also 3rd party and not supported here.
update for all, tripplite helped update the firmware and all works as it should 4k @3840 x 2160 x 60 on both input channels