Which one uses less power/battery, X200s or X201s?

[RealBlackStuff]

I have an X200s with SL9400 (1.86GHz) CPU and an X201 with i5-540M (2.53GHz) CPU, both with 4GB RAM.
Both also have an X200s lid with LED-WXGA+ (1440x900).
Q1: is the X201 with X200s LED-WXGA now actually an X201s?

So far I only have one 9-cell 47++ Panasonic battery and one SSD with W7/Pro 32-bit (more on the way).
Q2: which one should use less battery, X200s or X201s?

[Temetka]

The one you don't turn on will use less power.

Duh. C'mon man think about these things.

Seriously though, do you have a killawatt handy? If not I *think* hwinfo can monitor power usage iirc.

[TonyJZX]

you dont need a multimeter or whatever

http://cpuboss.com/cpus/Intel-Core2-Duo ... re-i5-540M

Intel runs on tick tock and the move to 1st gen Arrandale saw a significant improvement in performance at the cost of heat and power.

Core2Duo for all its faults, did sip power at the very end on the slimline cpus.

I do not expect to save power with my 1st and 2nd gen i5/i7 types.

[600X]

Due to the newer and more efficient architecture, the X201 will consume less power. However, you must not forget that it has a higher TDP of 35W and turbo boost, so it will use more power than the X200s when you push it even slightly.

Basically, if you plan on using the machine in idle (like office), the X201 will use less power. Otherwise, the X200s will be better.

[FryPpy]

Q1: is the X201 with X200s LED-WXGA now actually an X201s?

No.

S-line uses LV or ULV while X - NV, MV CPUs.
Comparing power consumption of NV vs LV CPUs is not correct. But if you asking about real world experementation it have some sence.

PS
In terms of pure TDP: SL9400 = 13.8W vs 640LM = 21.3W (540M = 28.4W).
But Core 2 needs northbridge with GPU (GM45) + 12W...

[bit_twiddler]

I have an X200s running Linux with no particular optimizations and 1 spinning hard drive
and I get about 7.3 watts at idle on battery (wifi on, but nothing happening.) It's hard to
imagine a more efficient machine without going to a Haswell or Broadwell with an SSD and DEVSLP.

I think the display is the main power user at idle. I'd be surprised to see a big
difference between the 2, even though one of your machines is not a LV CPU.

[ajkula66]

Q2: which one should use less battery, X200s or X201s?

My money would go on X200s, although I presume that the difference would not be a drastic one. Given that your X201 is really not "s" when it comes to the CPU, X200s should be a clear winner.

[RealBlackStuff]

Thanks for all your answers.
As soon as I have time, I'll swap SSD + battery over from X200s to X201, making notes for both machines.
Stay tuned.

[jaspen-meyer]

It will be 'too close to call'. There are a lot of variables involved. At a given work load one may
outperform the other, but at another work load you'll get the opposite. Same goes for a given
screen brightness. Different fan models will skew results this way or that. Variance in OS and drivers, and software will play a role. How much you use the mouse makes a big difference (every pixel moves kicks the cpu into a non-idle power state), etc, etc.

[X20055]

Had both, x200s was more power, heat and noise efficient. The difference was not that huge but significant - expect at least 2-3 hours less.

By the way, tested were sl9400 vs i7-620m, both HDD unplugged and exactly same Linux running from RAM. You can search my posts afaik I wrote about it here, but don't take all the data seriously as results can vary.

Must add very odd thing, x201s using 2-3W more in Linux idle than in Win7, both installed on same SSD, both 64-bit with 8GB RAM. Could not find solution to this, my guess is that i7 Arrandale is odd processor not properly supported by Linux.

And last - not sure if I got different screen panels, both were 1440x900 - or it's because of vid cards, but seemed that x201s colors were very 'cold' and didn't look as nice as x200s. This can be adjusted by setting custom color schemes.