GroovyArcade 2013-02-24 & Radeon HD 6450

[duke_of_earl]

Hello everyone.

In my cabinet restoration project I wanted to use a Linux solution, and found that GroovyArcade worked great on my previous tests. Now I have decided to upgrade the motherboard, memory and CPU on the computer that will go inside the cabinet. The new graphics card (Radeon HD6450) is being troublesome.

I remember I read on some other thread about Calamity having tested one, and that he made it work, so I decided to try it. On the first test, with the computer attached to a TV, I got this:



Believing the problem was related to the 15Khz setup, I then tried attaching it to a computer monitor... same effect! I suspected the card was damaged, I even took it back to the seller, that told me the card was working fine, at least under Windows. That made me think it could be a generic Linux problem, and after searching the net I found out it's a quite common problem with that card, that can be solved by disabling kernel modesetting (not useful for setting the 15khz resolutions), or activating the Radeon DPM support (available only on kernels 3.11 or later).

I confirmed it was the case by booting a Ubuntu 13.10 Live CD with the default parameters (same artifact on screen) and with radeon.dpm=1, that worked fine. So my next step is to try to boot my previous GroovyArcade installation with a more recent kernel and see if it works. Will report back when I do.

[ufoufo512]

I am using 6450 myself with Groovy Arcade Linux. Works great with min dotclock 8. I do get corruption if the arcade monitor vsize is too big. Better have small margins instead . I am not around my cab in following days, but I can make some more tests & info once home.

[ufoufo512]

I did have to disable boot splash screen, though. Having it enabled locked the system somewhere during the boot.

[ves]

Hello, you can try add options radeon dpm = 0 at  this file /etc/modprobe.d/radeon.conf

[duke_of_earl]

Hello, you can try add options radeon dpm = 0 at  this file /etc/modprobe.d/radeon.conf

Hello, ves, I have finally made it work. Actually, for my HD6450 to work, DPM must be enabled. I had previously enabled it by manually editing the boot entry on GRUB, but your method of modifying modprobe parameters is much easier, I tried it and it works. So the modification should be:

options radeon dpm = 1

By the way, DPM will be enabled by default on newer kernel versions, without the need for that fix. What kernel version will be included on the next version of GroovyArcade? I will test that new ISO as soon as it's available.