default depth too high in xorg.conf for Neomagic MagicGraph 256AV

[Dean Moreton]

After installing xubuntu on an old 390X IBM Thinkpad, the display was very slow updating, with scrolling and window moving painfully glitchy. This behaviour was not evident in Windows XP on this laptop, nor other Linux distros.

The laptop has a (according to xorg.conf) NeoMagic Corporation NM2200 [MagicGraph 256AV] using the "neomagic driver" and on my install was configured to use a DefaultDepth of 24bit. After checking another distros install on this hardware(in which this display updated smoothly) I noticed its default depth was set to 16.

I then modified xorg.conf to DefaultDepth 16 in xubuntu, restarted X and now display is smooth.

After googling it seems the chip does support 24bit, however the performance is poor. Therefore I think default should be 16 for this chip as often xubuntu is suggested as a good distro for lower spec machines, but initial impressions are that the hardware is not up to it. I believe this chipset may be quite common with older laptops.

[Caroline Ford (secretlondon)]

->xorg

On my 380ED Thinkpad it also gets the depth wrong and I end up with a massive resolution. Changing to 16 bit gives me 800x600..

[Mark Florian (markrian)]

Confirmed. I have a Toshiba 7020CT with the Neomagic MagicGraph 256AV card also (nm2200). Setting the bit depth to 16 makes scrolling/window movement smooth.

[Leo Iannacone (l3on)]

Confirmed on IBM ThinkPad 390X.

I had to change the set-up of color to 16bit in Xorg. It seems to work with 1024x768 resolution.

[Mark Florian (markrian)]

that (2D)acceleration is only supported up to 16 bits is documented in the driver. Higher bit depths become unusably slow, as bad as or worse than vesa.

[Timo Aaltonen (tjaalton)]

The manpage says that NM2200 and newer should be accelerated on 24bit. Please attach your Xorg.0.log.

[Timo Aaltonen (tjaalton)]

No reply, closing the bug.

[OliFre (freyermuth)]

Can confirm this bug with an older Toshiba-Notebook and xUbuntu. Was just wondering why everything was so slow, found this bug, changed default depth and everything is fast again.

[Timo Aaltonen (tjaalton)]

Could you try a newer release which doesn't install an xorg.conf anymore, like 9.10 or Lucid alpha1. Then we'd see if the default is right, and adjust that in the driver accordingly.

[Bryce Harrington (bryce)]

We're closing this bug since it is has been some time with no response from the original reporter. However, if the issue still exists please feel free to reopen with the requested information. Also, if you could, please test against the latest development version of Ubuntu, since this confirms the bug is one we may be able to pass upstream for help.