Thinkpads Forum

One option under BIOS to disable the Multi-Core processing -> to a Solo Core processing.

Anyone tested with its performance and heat dissipation rate?
As well as the battery life using a Solo Core.

T7300 2.0Ghz, reported power consumption is 35W,
disabled multi-core processing meaning that 17W power consumption which is similar to L7500 ??

is this ideal in real life?

TDP does not equal normal power consumption.

My pentium m has a TDP of 21w, but the entire laptop uses 9-12w.

So you will be halving something, but that something will be very small. How small I'm not sure (something as small as 1w still makes a difference for something like an X60).

I have tested single and dual core with 686-smp and 64bit Linux. Single core and 686 does drop consumption by around 2 watts vs 64bit and dual core -- a very big deal. Consumption using cpufreqd, ondemand, or conservative CPU speed control on 686 with single vs dual cores seems to even out in the end -- I don't feel making BIOS changes when going unplugged is worth it, though unless you are taxing your OS the speed decrease isn't a big deal, either.

The Santa Rosa System combined with Intel's Core 2 Duo processors feature a number of very nifty energy saving and cpu speed throttling functions.

Unless you really are obsessed with achievieng the absolut minimal power draw, you should not really disable the second core. The energy/heat savings achieived are disproportionatilly small compared to the loss in computing speed.

Disable core 2 duo, saving a 2W/ usage really make a significant difference

gunston wrote:Disable core 2 duo, saving a 2W/ usage really make a significant difference

In an energy optimized scenario on an X61s the notebook will probably use around 11 Watts. A 2W reduction roughly translates to 15% in reduced energy. However, disabling the second core translates almost into a 50% performance loss in peak load scenarios.

The % energy reduction when it comes to an X61 is even less, while the loss in peak load performance is the same.

If your main concern was achieving extermely low energy use, one should have gone for a notebook featuring an ULV CPU instead.

gunston wrote:...one should have gone for a notebook featuring an ULV CPU instead.

Too sad, in fact non of the Thinkpad lineup does offer ULV processor, only Panasonic Toughbook CF-W7 does.

gunston wrote:

gunston wrote:...one should have gone for a notebook featuring an ULV CPU instead.

Too sad, in fact non of the Thinkpad lineup does offer ULV processor, only Panasonic Toughbook CF-W7 does.

The W7 (and T7) seem like very nice machines. However, the coming Thinkpad X300 will feature an ULV 1.2 GHz CPU.

doesn't the C2D turn off one core and lower the voltage/frequency for the other normally without hacks? Or is that just the Mac Air one only? I thought i read that the C2D CPUs had that as a new feature.

Macair one CPU, or next generation thinkpad X300 with 45nm Processor (stated that it has even lower power consumption).

but not fancy wide screen option for X300 thinkpad

jketzetera wrote:

gunston wrote:Disable core 2 duo, saving a 2W/ usage really make a significant difference

In an energy optimized scenario on an X61s the notebook will probably use around 11 Watts. A 2W reduction roughly translates to 15% in reduced energy. However, disabling the second core translates almost into a 50% performance loss in peak load scenarios.

The % energy reduction when it comes to an X61 is even less, while the loss in peak load performance is the same.

If your main concern was achieving extermely low energy use, one should have gone for a notebook featuring an ULV CPU instead.

I have no problem getting to 8.5W on battery doing MSoffice-type stuff. I can get under 8W if I try hard. Both cores on.

8.5W is possible when leaving your thinkpad untouch.

X61s or X61 ?

x61s
1.8GHz
160GB 7200RPM disk
4GB RAM

Wi-fi off
BT off
Sound mute
8-bars of screen brightness