Jan Brandenburger Reporter
	Description • 14 years ago

User-Agent:       Mozilla/5.0 (Windows NT 6.1; WOW64; rv:2.0) Gecko/20100101 Firefox/4.0
Build Identifier: Mozilla/5.0 (Windows NT 6.1; WOW64; rv:2.0) Gecko/20100101 Firefox/4.0

My notebook is an Acer Aspire 5820TG with two graphic cards (Intel HD and ATI HD 5650 1GB), called "Hybrid Graphic".
You can switch between these graphic cards to save power (Intel) or to use CAD applications (ATI).
If you switch to ATI you get a black screen in the area, where the website is normally displayed.
Both of the graphic drivers are up-to-date.
I have no problems with Chrome, IE9, Opera or other applications.

Reproducible: Always

Steps to Reproduce:
1.Start Notebook with Intel HD graphic
2.Open Firefox 4.0 with e.g. "www.gmx.net" and "www.google.de"
3.Switch to ATI graphic
4.You see a black area instead of the website (if not press F5 or open a new tab)
5.if you start a "second" Firefox, you´ll see the same problem
6.You have to close all firefox.exe and start firefox again to solve the problem

	Matthias Versen [:Matti]
	Comment 2 • 14 years ago

Please post the graphic section from about:support

	[not reading bugmail]
	Comment 3 • 14 years ago

you can turn off hw acceleration in options menu, advanced section in the meantime.

	Jan Brandenburger Reporter
	Comment 4 • 14 years ago

(In reply to comment #2)
> Please post the graphic section from about:support

Okay, 

part 1: about:support using Intel chip     
--------------------------------------------------------------------------      
Karten-Beschreibung Intel(R) HD Graphics
Vendor-ID 8086
Geräte-ID 0046
Karten-Ram Unknown
Karten-Treiber (driver) igdumd64 igd10umd64 igdumdx32 igd10umd32
Treiber-Version (driver version) 8.741.1.6000
Treiber-Datum (date of driver release) 10-21-2010
Direct2D aktiviert false
DirectWrite aktiviert false (6.1.7600.16763, font cache n/a)
WebGL-Renderer Google Inc. -- ANGLE -- OpenGL ES 2.0 (ANGLE 0.0.0.541
GPU-beschleunigte Fenster (GPU-acellerated windows) 1/1 Direct3D 9

-------------------------------------------------------------------------------

part 2 using ATI-graphic card:

----------------------------------------------------------------------------
Grafik

Karten-Beschreibung ATI Mobility Radeon HD 5650
Vendor-ID 1002
Geräte-ID 68c1
Karten-Ram 1024
Karten-Treiber atiu9p64.dll atiuxp64 atiuxp64 atiu9pag atiuxpag atiuxpag atiumdva atiumd6a atitmm64
Treiber-Version 8.741.1.6000
Treiber-Datum 10-21-2010
Direct2D aktiviert false
DirectWrite aktiviert false (6.1.7600.16763, font cache n/a)
WebGL-Renderer Google Inc. -- ANGLE -- OpenGL ES 2.0 (ANGLE 0.0.0.541)
GPU-beschleunigte Fenster 0/1

	Jan Brandenburger Reporter
	Comment 5 • 14 years ago

(In reply to comment #3)
> you can turn off hw acceleration in options menu, advanced section in the
> meantime.

Thank you for this hint, it works!!

Uncheck "Hardwarebeschleunigung verwenden, wenn verfügbar" (using hw acelleration, if available) solves the problem.

	[not reading bugmail]
	Comment 6 • 14 years ago

Hmm, That hybrid functionality is kinda of a new concept in the graphics space.  Intel usually has a more worse experience with Firefox then ATI which is for the most part better, so this is interesting.  

cc'ing bas

	Tor Klingberg
	Comment 7 • 13 years ago

I get the same problem with a similar notebook as Jan. If I switch back to Intel graphics, Firefox goes back to normal. It seems the graphics is somehow tied to the chip, and it goes black when the other chip is activated.

	boris
	Comment 8 • 13 years ago

(In reply to Dennis "Dale" Y. [:cuz84d] from comment #6)
> Hmm, That hybrid functionality is kinda of a new concept in the graphics
> space.  Intel usually has a more worse experience with Firefox then ATI
> which is for the most part better, so this is interesting.  
> 
> cc'ing bas

I would see it the other way round, having a laptop that is ~4 years old with switchable graphics.
Utilizing GPU resources in Firefox is a new concept that is not well enough implemented - in Firefox.
Switching off HW-accelleration significantly affects browsing speed and reduced Firefox to a 2nd generation browser.

BTW for all that want to use the browser with HW-accelleration activated: Simply restart the browser - it will become aware of the current configuration and everything will work. However, when you switch back the same will happen (black regions).

Considering this behavior it seems that the code is not aware of that a change of processing hardware can happen during operation and leaves the pointers in the memory space of the GPU it originally started with.

Furthermore: does this only happen in MS-windows, or are other OSs affected as well?

	boris
	Comment 9 • 13 years ago

The fact that the internal GPU-check of Firefox does not work is also seen if one tries about:support and looks at the GPU section after switching GPUs while leaving FF running.
- Be aware that this only works when hw-acceleration is switched off (since the screen will not be updated due to the bug in accelerated mode)

	maxiumpix
	Comment 10 • 13 years ago

Another way to address this issue is to block the ability to switch graphics if the program is running. 

This is how IE handles it. (badly IMHO)