[opensuse] Dual / quad core
Hi, I think i fried my system (again ;) and was considering the config for my next system. When looking at the power consumptions of the multi-core CPU's, i was wondering if it is possible to power-down one or more cores when the system load does require them... A quad core is nice, but needs over an 100watt of energy, that has to vent-out aswell... (Or am i talking nonsens?) -- To unsubscribe, e-mail: opensuse+unsubscribe@opensuse.org For additional commands, e-mail: opensuse+help@opensuse.org
On Tuesday 04 September 2007 15:18, Hans Witvliet wrote:
Hi,
I think i fried my system (again ;) and was considering the config for my next system.
When looking at the power consumptions of the multi-core CPU's, i was wondering if it is possible to power-down one or more cores when the system load does require them...
Idle CPUs (or cores) naturally consume less power.
A quad core is nice, but needs over an 100watt of energy, that has to vent-out aswell...
I was under the impression that the Core 2 processors were more energy efficient (as well as far better performing) than their predecessors. In any event, peak power consumption occurs only during 100% CPU utilization (and that power consumption depends somewhat on the mix of instructions, i.e., which portions of the CPU's processing logic is active). When the CPU is idle, it's power consumption (and thus its heat output) are much less. Keep in mind, too, that the "chipset" consumes quite a bit of power, independent of what kind of CPU it serves. These are things like the memory controller hub, MCH, the I/O controller hub, ICH (usually combined) and especially the GPU as well as other chips contribute significantly to the system's power consumption. Check out <http://www.pcstats.com/articleview.cfm?articleid=2097&page=3> for interesting power consumption measurements for various current CPUs, including the Core 2 Duo. Randall Schulz -- To unsubscribe, e-mail: opensuse+unsubscribe@opensuse.org For additional commands, e-mail: opensuse+help@opensuse.org
In any event, peak power consumption occurs only during 100% CPU utilization (and that power consumption depends somewhat on the mix of instructions, i.e., which portions of the CPU's processing logic is active). When the CPU is idle, it's power consumption (and thus its heat output) are much less.
I have a dual core.. and under regular use the CPU barely gets above room temp... well.... it sits at about 30 C. Regular use... email, web browsing... low demand stuff. If I load it up and do something that pegs one CPU to 100%, the temp rises to about 38 C. If I max both CPUs to 100% and leave it, the temp rises to 45 C to 48 C. So... if you're planning on doing things that will max out the dual or quad core, then things will get hot. If you're using it more... for normal desktop type use, the computer will probably actually run cooler overall, and be a whole lot more usable when it gets busy doing something on one CPU. C. -- To unsubscribe, e-mail: opensuse+unsubscribe@opensuse.org For additional commands, e-mail: opensuse+help@opensuse.org
On Wednesday 05 September 2007 00:10, Clayton wrote:
In any event, peak power consumption occurs only during 100% CPU utilization (and that power consumption depends somewhat on the mix of instructions, i.e., which portions of the CPU's processing logic is active). When the CPU is idle, it's power consumption (and thus its heat output) are much less.
I have a dual core.. and under regular use the CPU barely gets above room temp... well.... it sits at about 30 C. Regular use... email, web browsing... low demand stuff. If I load it up and do something that pegs one CPU to 100%, the temp rises to about 38 C. If I max both CPUs to 100% and leave it, the temp rises to 45 C to 48 C.
These temperatures would make a Pentium shiver.
So... if you're planning on doing things that will max out the dual or quad core, then things will get hot.
It's all relative. The Core 2 design is much more energy-efficient than its predecessors, including CPUs designed for portable use.
If you're using it more... for normal desktop type use, the computer will probably actually run cooler overall, and be a whole lot more usable when it gets busy doing something on one CPU.
If the system is assembled properly and the case ventilated properly, there's no problem, even if you're running SETI@home or Folding@home or any of the CPU-intensive distributed clients on every core.
C.
Randall Schulz -- To unsubscribe, e-mail: opensuse+unsubscribe@opensuse.org For additional commands, e-mail: opensuse+help@opensuse.org
On Wednesday 05 September 2007 03:10, Clayton wrote:
In any event, peak power consumption occurs only during 100% CPU utilization (and that power consumption depends somewhat on the mix of instructions, i.e., which portions of the CPU's processing logic is active). When the CPU is idle, it's power consumption (and thus its heat output) are much less.
I have a dual core.. and under regular use the CPU barely gets above room temp... well.... it sits at about 30 C. Regular use... email, web browsing... low demand stuff. If I load it up and do something that pegs one CPU to 100%, the temp rises to about 38 C. If I max both CPUs to 100% and leave it, the temp rises to 45 C to 48 C.
So... if you're planning on doing things that will max out the dual or quad core, then things will get hot. If you're using it more... for normal desktop type use, the computer will probably actually run cooler overall, and be a whole lot more usable when it gets busy doing something on one CPU.
C. In order to decide on a running temperature, you need to find out what the temperature of the internal silicon to the temperature of the case is, that is the delta T (C) is from the internal device to the case. This should be available in a data sheet for the device, which is probably on the net somewhere. What you are measuring, of course, is the case temperature, not the temperature of the chip inside. In general, you would like to keep the temperature of the silicon below 100 degrees C. If your system can do that, everything should work fine, basically forever. If not, you need a better cooling system.
--doug, wa2say -- Blessed are the peacemakers ... for they shall be shot at from both sides. --A.M. Greeley -- To unsubscribe, e-mail: opensuse+unsubscribe@opensuse.org For additional commands, e-mail: opensuse+help@opensuse.org
Hi, Hans Witvliet wrote:
When looking at the power consumptions of the multi-core CPU's, i was wondering if it is possible to power-down one or more cores when the To answer this question: If cpu hotplug is enabled, then you find within /sys/devices/system/cpu/cpuX/ the file 'online'. With that file you can enable or disable the usage of the core/cpu. system load does require them... A quad core is nice, but needs over an 100watt of energy, that has to vent-out aswell...
Regards, -- Patrick Kirsch - Quality Assurance Department SUSE Linux Products GmbH GF: Markus Rex, HRB 16746 (AG Nuernberg) -- To unsubscribe, e-mail: opensuse+unsubscribe@opensuse.org For additional commands, e-mail: opensuse+help@opensuse.org
participants (5)
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Clayton -
Doug McGarrett -
Hans Witvliet -
Patrick Kirsch -
Randall R Schulz