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I've been using Fedora 15 for a couple months now and haven't had any problems. Last week I switched desks and got a new monitor, and now all of a sudden it will randomly freeze up.

Also sometimes without freezing it will make all title bars (including the system bar at the top of the screen) and system images (such as the images for the launcher on the left side of gnome 3) plain blue, and any text on them is just blocked out in darker blue.

It usually freezes some time after everything turns blue. I can switch to another terminal using Ctrl + Alt + F2 and reboot. I checked the messages log and found this:

kernel: [ 1706.856599] [drm] nouveau 0000:01:00.0: PGRAPH - TRAP
kernel: [ 1706.856602] [drm] nouveau 0000:01:00.0: PGRAPH - ch 4 (0x0000b45000) subc 5 class 0x8297 mthd 0x0e08 data 0x04380000
kernel: [ 1706.856611] [drm] nouveau 0000:01:00.0: VM: trapped read at 0x20ff202000 on ch 4 [0x00000b45] PGRAPH/TEXTURE/00 reason: PT_NOT_PRESENT
kernel: [ 1706.856695] [drm] nouveau 0000:01:00.0: magic set 0:
kernel: [ 1706.856698] [drm] nouveau 0000:01:00.0:  0x00408904: 0x8008700f
kernel: [ 1706.856700] [drm] nouveau 0000:01:00.0:  0x00408908: 0x20ff2020
kernel: [ 1706.856702] [drm] nouveau 0000:01:00.0:  0x0040890c: 0x40000e04
kernel: [ 1706.856703] [drm] nouveau 0000:01:00.0:  0x00408910: 0x20200000
kernel: [ 1706.856705] [drm] nouveau 0000:01:00.0: PGRAPH - TRAP_TEXTURE - TP0: Unhandled ustatus 0x00000003
kernel: [ 1706.856707] [drm] nouveau 0000:01:00.0: PGRAPH - TRAP
kernel: [ 1706.856709] [drm] nouveau 0000:01:00.0: PGRAPH - ch 4 (0x0000b45000) subc 5 class 0x8297 mthd 0x1b0c data 0x1000f010
kernel: [ 1706.856716] [drm] nouveau 0000:01:00.0: VM: trapped read at 0x20ff202000 on ch 4 [0x00000b45] PGRAPH/TEXTURE/00 reason: PT_NOT_PRESENT

My system admin thought it might be some loose RAM, but I tried taking out and putting back in all my RAM sticks and it didn't work.
I am using a graphics card that I took off an old machine, under Fedora System Settings it says my graphics driver is: Gallium 0.4 on NV86.

Is it time to upgrade to a new graphics card? If so it's not a big deal, I can get one that will fit my needs for around $50. I'm just not sure if that's the problem, or if it can be fixed with a different way.

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While there are some bug reports of nouveau freezes, none of them fit your description -- You could add one, I suppose. (Before you get a new graphics card, you could also give Fedora 16 a try.) – sr_ Feb 7 '12 at 15:12
up vote 1 down vote accepted

It may be the nouveau driver, which many people advise to void like the plague. This link explains how to disable it and replace it with the native nVidia drivers.

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Thanks, I had my system admin help me through the process of compiling the native nvidia drivers from their website in run level 3. Works great now! – Kyle Feb 9 '12 at 14:16
If so, would you mind accepting the answer? Thanks – Alien Life Form Feb 9 '12 at 16:47

There was a workaround for some other bugs occuring with the nouveau driver which also spitted PGRAPH_TRAP errors. Just add this arg to the kernel invocation in GRUB or whatever loader you're using:

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