[CentOS] Problem with graphics on latest CentOS 6

Mon Oct 30 19:38:37 UTC 2017
Alfred von Campe <alfred at von-campe.com>

Am I the only one seeing this issue?  Or is it that so few people are still running CentOS 6.x?  Quick summary, on a very recent Dell motherboard using the on-board vide and booting the latest CentOS 6 kernel with the “vga=xxx” parameter set to any non-default value results in unusable X11 graphics.

Alfred

> On Oct 29, 2017, at 15:29, Alfred von Campe <alfred at von-campe.com> wrote:
> 
> The thread "Problems with kernel-3.10.0-693.5.2.el7.x86_64” reminded me that I have a similar problem but on the latest CentOS 6 kernel I’ve been meaning to report.  Here is the relevant system information:
> 
> Linux ssg003.bose.com 2.6.32-696.13.2.el6.i686 #1 SMP Thu Oct 5 20:42:25 UTC 2017 i686 i686 i386 GNU/Linux
> 
> 00:02.0 VGA compatible controller: Intel Corporation Device 5912 (rev 04) (prog-if 00 [VGA controller])
>        Subsystem: Dell Device 07a2
>        Flags: bus master, fast devsel, latency 0, IRQ 11
>        Memory at f6000000 (64-bit, non-prefetchable) [size=16M]
>        Memory at e0000000 (64-bit, prefetchable) [size=256M]
>        I/O ports at f000 [size=64]
>        Expansion ROM at <unassigned> [disabled]
>        Capabilities: [40] Vendor Specific Information: Len=0c <?>
>        Capabilities: [70] Express Root Complex Integrated Endpoint, MSI 00
>        Capabilities: [ac] MSI: Enable- Count=1/1 Maskable- 64bit-
>        Capabilities: [d0] Power Management version 2
>        Capabilities: [100] #1b
>        Capabilities: [200] Address Translation Service (ATS)
>        Capabilities: [300] #13
> 
> I have about 100 Dell desktops deployed with CentOS 6 all using the built-in motherboard graphics.  But on a Dell Optiplex 5050 with an Intel(R) Core(TM) i7-7700 CPU @ 3.60GHz CPU and the above graphics card, the X11 login screen is all distorted and unusable.  There is a simple solution: if I remove the "vga=0x31b” parameter from the kernel boot command it works just fine.  However, I would prefer to have a usable alternate console on our 1900x1200 monitors, but any value I tried for the vga parameter results in a distorted login screen.
> 
> Any ideas what may be causing this?  This is only an issue on the very latest chipset.  On the next most recent Dell desktops we have (Intel(R) Core(TM) i5-4590 CPU @ 3.30GHz) I do not have this issue.  Here is the VGA controller info:
> 
> 00:02.0 VGA compatible controller: Intel Corporation Xeon E3-1200 v3/4th Gen Core Processor Integrated Graphics Controller (rev 06) (prog-if 00 [VGA controller])
>        Subsystem: Dell Device 05a4
>        Flags: bus master, fast devsel, latency 0, IRQ 28
>        Memory at f7800000 (64-bit, non-prefetchable) [size=4M]
>        Memory at e0000000 (64-bit, prefetchable) [size=256M]
>        I/O ports at f000 [size=64]
>        Expansion ROM at <unassigned> [disabled]
>        Capabilities: [90] MSI: Enable+ Count=1/1 Maskable- 64bit-
>        Capabilities: [d0] Power Management version 2
>        Capabilities: [a4] PCI Advanced Features
>        Kernel driver in use: i915
>        Kernel modules: i915
> 
> Does anyone else have a similar issue and found a better solution?
> 
> Alfred