Thread: ANNOUNCE: Diablo-Turbo first beta available
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maacruz is offline maacruz
2011-02-13 , 11:54
Posts: 1,101 | Thanked: 1,184 times | Joined on Aug 2008 @ Spain
#17
Originally Posted by auouymous View Post
Originally Posted by heavyt View Post
Are you saying the only way to change the frequency is by editing /etc/kernel-dt-tunables, that it is set at 333MHZ no matter if the unit is idle or not? If so will that have an effect on the battery charge?
I think he said, in the other thread, that when the DSP is active the cpu can't exceed 333MHz but this patch allows the cpu to reach 400MHz but the DSP has to be clocked slower than it would if the cpu was at 333MHz. So I'm guessing it has no effect on battery.
When the DSP is active the CPU is set at 333 MHZ and the DSP at 220 MHZ, no more, no less, no matter if the unit is idle or not, it is a hardware design issue, so this happens no matter the kernel. This patch allows to set the CPU at 400 MHZ at the cost of setting the DSP at 133 MHZ.
When the DSP is not in use, the governor can change the CPU frecuency.
Regarding effect on battery, the CPU takes more power than the DSP, so the 400/133 setting shortens battery life (about 25% less) wrt the 333/220 setting.
Except when playing videos, where you get about the same battery life, but smoother playback.
Last edited by maacruz; 2011-02-13 at 12:00.
 

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