Operating system on the computer is Debian unstable (siduction). The computer is used for scientific activities: Programming in Python, Matlab, C / C ++. There are the usual activities such as Intenet, Mail, Office, LaTeX, image processing.
The demands on the graphics card were relatively low:
1) absolutely quiet
2) running multiple monitors
3) no Nvidia (since abschmierte me the computer at high CPU load with all sorts of Nvidia drivers versions repeatedly)
The Sapphire Radeon HD6450 graphics card meets all the above requirements without problems. Used the open source driver (xserver-xorg-video-radeon) with additional binary firmware (firmware-linux-nonfree). The two monitors are connected via DVI and HDMI (with HDMI-DVI adapter) and have been established for multi-monitor operation in KDE.
As negative I found the rather high temperature of the graphics card is idle. Although the computer has been equipped with a power supply fan and a case fan, but reaching the graphics card in idle a temperature of about 78 ° C. Thus the whole computer the graphics card heated up quite strongly.
This problem I solved by I added another 12cm fan in the housing, the cold air from outside sucks active. I also have the power profile of the graphics card to "medium" limited: achieved by the line "echo mid> / sys / class / drm / card0 / device / power_profile" in /etc/rc.local.
Since the graphics card runs at a temperature around 60-63 ° C.
Conclusion:
1) The graphics card meets my needs. The computer is very quiet. There are no crashes under heavy CPU load, as before with Nvidia drivers.
2) The graphics card reached quite a high temperature in the idle state, and probably much higher temperatures under load.
Is therefore to look very meticulously sufficient cooling in the housing. Under certain circumstances, additional case fans have to be installed.
3) final evaluation: Good
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[ADDENDUM | 10.09.2013]
Meanwhile, a lot has changed with regard to the driver situation. AMD has the long-awaited power management implemented after a lengthy development work with free drivers and the Linux kernel, which can be used Kernel 3:11 (possibly with kernel parameters radeon.dpm = 1 boot).
I have after a kernel upgrade enabled on my desktop the new power management and am very satisfied! The graphics card is going great and cooler than before: in idle state, the temperature is now at 56 ° C.
