virtualbox.org

Hi,

I've been using VBox for many years now and I really like it. Recently I upgraded my System to 2x LG 34uc88 monitors with 21:9 aspect ratio and 3440x1440 resolution. Now for some reason my guest system cannot handle the 2 VBox monitors correctly when they are full size. The result is a bit odd, it looks like the screens don't use the correct amount of pixels per line. For some reason this only affects the desktop client area and not the task bar of ubuntu (the client system). This only happens when I have both VBox monitors in use and they are over some threshold width. The Treshold is about 1+2/3 Monitor... so around ~5700pixels, if I scale one of the VBox windows down everything works just fine. My first thought was maybe the VRAM is too small, so I increased it by command line to 256MB instead of the max. slider value of 128MB. This made no difference. I updated VBox to the recent version and installed the corresponding Guest Edition, but still no difference. So I'm a bit lost now, and don't know any further...

I've attached a snippet of the screens top right corner of one screen (other screen looks identical) so you can see it yourself.

Host OS is Win10 Pro x64 with:
GTX1080 8GB
2x E5-2643
256GB RAM
(it should be powerfull enough...)

Client OS:
Ubuntu 14.04 LTS 64Bit
2 Virtual monitors
256MB VRAM
3D acceleration enabled
Scale factor: 100%

Any help appreciated.

Regards
Maik

Please provide a VM log file. With the VM fully shut down, right click it in GUI. Select "Show Log" and save "VBox.log" (ONLY) to a zip file. Attach the zip here.

Ok, here is the log...

Ok, you don't seem to have made any of the obvious errors, and virtually the same graphics card as mine, so I'm left to suspect some kind of driver problem in the guest, though I'm not sure what it could be.

I rather doubt that the host is relevant here, so I'm moving this topic to "Linux Guests". Perhaps people with more Linux experience will respond there.

In the meantime, perhaps you could clarify whether all VMs are affected, or only this one. Particularly useful info if you have more than one guest OS type.

I really don't do Windows but I would think this might be a real issue with video since the guest actually uses the host graphics via hooks. Perhaps a signed version of the driver might help.

mpack wrote:Ok, you don't seem to have made any of the obvious errors, and virtually the same graphics card as mine, so I'm left to suspect some kind of driver problem in the guest, though I'm not sure what it could be.

That's good to know and a bit worrying as I thought it might just be a configuration issue.

Perryg wrote:

Code: Select all

00:00:04.073564 supR3HardenedErrorV: supR3HardenedScreenImage/LdrLoadDll: cached rc=VERR_LDRVI_NOT_SIGNED fImage=1 fProtect=0x0 fAccess=0x0 cHits=512 \Device\HarddiskVolume11\Program Files (x86)\LG Electronics\OnScreen Control\bin\ScreenSplitterHook64.dll
00:00:04.073621 supR3HardenedErrorV: supR3HardenedMonitor_LdrLoadDll: rejecting 'C:\Program Files (x86)\LG Electronics\OnScreen Control\bin\ScreenSplitterHook64.dll' (C:\Program Files (x86)\LG Electronics\OnScreen Control\bin\ScreenSplitterHook64.dll): rcNt=0xc0000190

I really don't do Windows but I would think this might be a real issue with video since the guest actually uses the host graphics via hooks. Perhaps a signed version of the driver might help.

I've removed the OSD driver for the monitors as it's just a tool to change monitor settings from within windows. And it's pretty bad...The result is the same though.
In the mean time I tested with different VMs, and all of them have this issue, although they are just ubuntu 14 & 16. I've installed a fresh version of Ubuntu 16 and as soon as I install guest additions I get the same results. However without guest additions I can use both monitors full size (but of course ridiculoulsly slow).

I've found another problem with my main VM that is even worse (some others have this problem too, but not all of them):
When I start up the VM in full size (even if I only use 1 guest monitor), the clients graphics are extremely slow. It's like it's using software emulation. Winndow Animations are jumping in steps, scrolling is stepping too... It's actually not usable anymore. I figured out to workaround this by resizing the VM window to something smaller before shutting down the VM. When I start the next time I get full graphics speed.

This problem affects basically all newer VMs. The only VMs that don't have this problem are old Ubuntu 14 VMs that had previously Vbox 4.x guest additions on it. Even after updating the guest additions they don't show the problem.

I've attached a recent log with the current status after playing around.

Just from comparing to VMs, I can already see what's causing the refresh rate problem in my main VM:

Broken:

$ xrandr
Screen 0: minimum 320 x 200, current 5360 x 1391, maximum 16384 x 16384
VGA-0 connected primary 3440x1387+0+0 (normal left inverted right x axis y axis) 0mm x 0mm
   3440x1387       4.8*+
...

Working:

xrandr
Screen 0: minimum 64 x 64, current 5158 x 1387, maximum 32766 x 32766
VGA-0 connected primary 3440x1387+0+0 0mm x 0mm
   3440x1387      60.0*+
...

For some reason the broken one doesn't get the right refresh rate. But I've no idea how to fix that

AFAIK, refresh rate isn't relevant to a virtual display - it doesn't do any refreshing. There is certainly a question of why two VMs are different. Are they the same guest OS?

They are both from the same Ubuntu image but the one that is working wasn't updated for some time. It really looks like it's a refresh problem though and the refresh rate is completely locked at startup and doesn't change. Like I said when I start the stuttering VM in a smaller window and maximize the window when it is running the graphics run at full speed.

Please repeat after me: refresh rate does not matter in a VM. It matters as much as the amount of oranges in your refrigerator Tuesday morning after a full moon.

Yeah, thanks for insulting me. Helps quite a lot to solve the problem. If you would read carefully, I wrote "It really looks like...", so I didn't say "it is that" but "it looks like it".

There have been hundreds and hundreds of messages about this and it seems like it always comes back, like you'd think that people don't search beforehand. I wanted to be as definitive and clear as possible. I wasn't trying to insult you and I apologize if it was perceived as such.