I have had a lot of angst about what to replace my iBook with, and I settled on the Lenovo U150. I have some observations which may be useful if you are considering whether to purchase it, or trying to get Linux to run on it.

It was drawing about 1.15A (according to its own monitor) while idle. This seemed ridiculous to me, given that I know there are processors which can truly scale down to a really low power level when idle. I did some research and the much-lauded Core 2 Duo is not one of them. Some of the Core 2 Duos can go into "deeper sleep" power saving mode and still draw up to 20W!!! I even tried booting in uniprocessor mode without any power savings. Intel truly needs to add a 200MHz mode to this processor line that draws on the order of 2W. I intend to do more research to find out if there isn't a way to underclock the FSB or something to get something lower than the 800MHz minimum mode that Linux reports.

That said, I found a substantial power savings:

iwconfig wlan0 power on

That turns on power management for the wlan0 driver. It basically saves 150-200mA in the idle condition! That's incredible! About 15% of my laptop's power profile going just towards not using power management! What a great feature that was!

So now it drawns about 0.95A most of the time while it is idle, which is substantially better. It still gets relatively hot (on the inside), at up to 47C active (i.e., prolonged skype video call) but typically around 40C. But on the outside, it is not really any hotter than the iBook, it is just running the fan more often.

Oh and I haven't run the battery all the way down yet but it seems plausible (assuming the battery monitor is any good) that this thing will now get 4-5 hours in Linux, which is as good as reviewers reported for Windows, so I am pleased. We'll see how long the battery survives, but for the moment it is such a dramatic improvement over anything my iBook has been capable of for years that it is a delight. It may be worthwhile to just accept a $100/year laptop battery tax, if I don't destroy this laptop in some other way first.

And _nothing_ stresses out this thing's CPU! I remember my Athlon XP 2500 (1.83GHz) would use more than 100% CPU (i.e., it fell progressively behind) encoding NTSC video with mencoder. This thing, I use its builtin webcam and I am able to encode at only about 20% CPU usage, even in the 800MHz mode!

So this thing pretty much flies on one core running at approximately half speed. That's fantastic. If only we could lower the idle power usage a little bit, I'd be totally enthralled. Either way, I'm glad that I opted for something better than the Atom, as I have not had to wait for anything yet. Even javascript is super fast. Woo!

I've been thinking about what made the iBook special that is lacking in the current laptop, and I have come up with a list:

• A complete absence of LEDs (I consider this an Apple feature)
• Silent operation
• ?Durability? (I'm assuming I'll be pulling cat hair out of the fan in fewer than 5 years)

In other news, I have been playing with Intel SpeedStep. On the Core 2 Duo it seems to be that the MSR has the following bits:

0x100000000

disable Intel Dynamic Acceleration (automatic overclocking with thermal limit)

0x8000

Divide the FSB by two (it is either 100MHz or 200MHz)

0x4000

Increase the multiplier by 0.5

0x0X00

X is the multiplier (6 is the minimum)

0x00XX

XX is the voltage, in some format like 0.70+0.016*XX

These values are set through MSR 0x199:

wrmsr -p0 0x199 0x100008608
wrmsr -p1 0x199 0x100008608

You can read the current status with:

rdmsr -p0 0x198

Note that you must use something like "cpufreq-set -f 800000" to turn off any dynamic CPU frequency governors or the kernel will override your settings.

I built up a little table by setting the MSR and then running a stupid little benchmark to verify it took effect. I also monitored (in a haphazard fashion, I suppose) the battery draw (current) meter on my laptop and recorded the minimum and maximum that I observed. ACPI provides a way for the BIOS to tell the kernel known-good values for the MSR, which i have labelled as "stock" in this table.

As you can see the thing comes with 800MHz, 1200MHz, and 1300MHz by default. I thought it was stupid that it could do 600MHz but the BIOS didn't support it. But now I know it doesn't matter. See, if you let the idle system settle long enough (these tests were mostly not idle) then it will draw as little as 0.95A, regardless of the CPU frequency. In other words, when it is in the HALT state at 1300MHz it is almost as efficient as when it is in the HALT state at 600MHz. Which sounds kind of neat but really it obviates SpeedStep because the converse is true: when it is in a HALT state at 600MHz it is as inefficient as at 1300MHz! Even reducing the CPU voltage doesn't have a significant effect.

So SpeedStep is basically useless and retarded, and only controls the maximum amount of performance and power consumption you will experience. If you don't use 1.3 billion cycles of CPU power then it won't draw any extra current no matter what the clock rate.

Verdict: it's not worth hacking the 600MHz mode into the driver.

This is a real disappointment because I had an Athlon XP 2500 desktop processor that did much better. At 1.83GHz, it was hot and drew so much current that it melted its power supply capacitors on the motherboard. Once the capacitors failed to a certain point, it would crash all the time so I was able to reduce it to ~500MHz and achieve a substantial savings. The thing ran cool, the power supply was not stressed, etc. My only consolation is that the Core 2 Duo probably draws less at peak utilization than the Athlon drew ever, but that's just a generation difference. These days, we ought to be able to do better. We ought to be able to set the CPU into an idle mode where it draws almost no current. As near as I can tell the CPU is the major consumer in this laptop, as it draws around 800mA in its most idle state with just the CPU, RAM, and display operating.

As an inspiration of what is possible, there is the Nokia n800. It operates around 300MHz peak and scales down to about 150MHz when it is not in use. Its CPU remains active at all times, even when it is "off". Which is pretty awesome because you can SSH into it or run monitoring tasks or whatever, even if it appears off. It gets about 4 days of idle battery life, but if you ask the CPU to perform then it can chew through the whole battery in a couple hours. This is more like what I would expect to see out of a decent mobile processor. The idle power consumption should be approximately zero, giving you a full day or so of battery life in general. Then if you run video games or whatever then it should burn up the battery.

I have had this laptop long enough that I can tell you a pretty definitive verdict about its quality.

The last PC laptop I had was an Averatec (uh, basically the same level of quality you would expect from Acer). It would constantly overheat to the point of crashing. It overheated to such an extent that it physically cooked its battery (Lithium is a very good battery technology, but heat is its achilles heel), so it would only get 20 minutes of battery life after only 18 months of usage. I had to patch the buggy BIOS (ACPI) to make it run the fan more, but it still overheated. It was loud. It would never do suspend successfully and its wireless was flakey until the day it died. Insult on top of injury: it was physically falling apart. I eagerly traded it to a friend for a Sawzall after only 18 months of ownership (my iBook lasted 5 years!) and he told me that it died completely a couple months after that.

So when I decided I could not stomach buying another Apple product, my fear was that buying another PC laptop would put me in the same position of having a really crappy laptop that I would hate for all the same reasons.

So by comparison, this laptop is pretty good. It has really only two flaws which keep pissing me off. One is that it overheats. The other is that it intermittently refuses to acknowledge that there is a device attached to the headphone jack. Which seems like small potatos but suggests a level of debugging was not applied to the analog circuits in the laptop. They probably had outstanding bugs and said "oh, fuck it, let's just ship this shit." Which Apple mostly doesn't do, or at least tries harder to hide.

But the overheating deserves some comments. It runs about 42C ideally, but like the Averatec the ACPI BIOS is not designed to keep it at 42C, and in fact doesn't seem to turn the fan to full strength until the laptop is over 50C. Or something. Anyways, at 50C parts of the laptop are uncomfortable to touch. Also at 50C the 802.11 becomes flakey. Basically, it throttles down to ~100kB/s max bandwidth. It still works, but it's frustratingly insufficient for regular loads. If you continue to utilize the laptop, it will happily get all the way up to 60C.

The real bonus of this laptop is that at 60C it still doesn't crash. The 802.11 chipset failure is in fact the only conspicious failure. And as an added bonus, the physical design of the laptop doesn't tend to heat the battery. I don't know exactly why but the battery is typically still cool to the touch even as the laptop's internals are burning up. So they mitigated all of the damage from overheating.

But it does still overheat. I will be glad to be rid of it. But it isn't physically falling apart. It doesn't crash (ever -- it is as stable as the iBook was), and its battery still works pretty well. So I'll probably have it for a good long time.

C'est la vie.

I should have bought a high-end netbook instead of a low-end laptop.

I have had the laptop for nearly a year now, and I feel pretty good about it actually. Its overheating is pretty retarded, and obnoxious, and I wish its idle consumption was much better.

But a key test of the overheating is the battery. At one year old, heavy use, it is still more than 3 hours in practice. Which is fine, hardly significantly diminished after a year. So even though it runs hot, it doesn't put this heat into the battery or it surely would be toast already.

The other test of overheating is crashing. And it is still rock-solid. It only crashes if I let the battery run down to 0. It has been 95 days since the last time that happened.

Also, I've gotten used to the speed. This laptop is, I'm pretty sure, the fastest computer I use on a regular basis.

So yeah...it's always warm and often hot. I once let it get up to 65C (149F) internally with my leg in front of its fan port, and the little blast of air coming out of the port became searingly hot, so I noticed and moved my leg. And the laptop didn't crash. *shrug*

I feel like I did the world a disservice with my previous post. I forgot to mention the one serious downside to this laptop, and it's a fuckin' doosey.

The keyboard sucks. If you push the key hard enough to "click" then it is only typically 90% as hard as is necessary to generate a software button press event. At one year out, some keys are substantially more difficult to press than others.

They've been failing from numerous causes. Somehow they concentrate cat hair at a certain point, which my iBook did not (even though they're very similar designs). And the tiniest bit of dust will cause them to make a crunching sound instead of a clicking sound, and no button press events whatsoever. So I am constantly prying the caps off to clean under them. The little plastic teeter-totters under the keys are very flimsy, and when they scaled the design down to make the arrow keys they simply shrank the plastic to fit the space rather than paying attention to basic engineering principles regarding the strength of plastic. The result is that one of the plastic teeter-totters split into 3 pieces with no effort whatsoever, so now I'm short a right arrow key.

To make matters worse, Lenovo parts are not super-widely available, and the keyboard is not easy to replace _at_all_. Both of these are surmountable problems but if the laptop lasts 5 years I don't want to go through this hassle 4 fucking times.

A keyboard is unfortunately a rather crucial component to a laptop. I can't believe Lenovo can't make one, they fucking suck.

From today's slashdot:

Computer manufacturer Lenovo has partnered with Swedish startup Tobii Technology to launch the world's first eye controlled laptop which will be on display as from today at CeBIT in Hannover.

They obviously figured out their keyboards suck but instead of fixing the problem they went nuclear on it.

I want to be absolutely explicit about this: Lenovo sucks.

I happened to see that Lenovo is releasing new products (imagine that), and the thought of anyone paying name-brand prices for Acer-quality garbage pissed me off so much I had to say this.

My biggest regret about my shitty laptop is that it cost me $800 so I don't want to think of it as disposable. If I'd bought the $300 Acer or Dell that I was originally looking at, I wouldn't be having this problem now, nearly 1.5 years later.

But I can say one good thing about my laptop. It gets real hot (hotter now than ever, especially since it's summer), but it doesn't dump the heat load directly onto the battery. As a result, the battery is still totally decent. Probably better even than the iBook's was after a year, which is really saying something. That is to say, I get a real 3-4 hours of use unplugged, with the stock battery. Considering that I drain it almost all the way about once a day on average, that's pretty fantastic!

The laptop has been falling apart for a while now. The plastic parts at the corners of the laptop picked up some damage and then started to separate. I figured that is just what happens to crappy plastic laptops. I mean, even my iBook's fancy acrylic shell eventually developed cracking at the corners (though never movement like this).

Today I diagnosed the problem. The screws were working themselves out on their own. On the one hand, that is pathetic. I've never had that happen on any consumer device before. On the other hand, yay. I repaired it.

Oh and -- it still overheats. It's so bad that sometimes it is physically painful to allow it to touch my leg.

I happened to see the Lenovo product page for the U150 today. It shows a photo of the thing with no battery in it, which makes it look very slick indeed. The irony -- I had just gotten through telling my friend that a laptop with a 10GHz processor and no battery capacity executes 0 instructions per second.

But I pondered, perhaps they have made a thin battery for it as a luxury add-on. So I clicked on the "shop for accessories" link that had a photo of a battery over it. The link failed to communicate to the shopping website that I was looking for U150 parts, so it showed me parts for all their other laptops. I told it to narrow it down by model number. The model number on this laptop is 6909. Alternatively it might be "QB09110415" (that is the number beside "MO:" on the sticker, not the one beside "S/N:", though it sure looks like a serial number to me).

The Lenovo website is very insistent that every Lenovo product has a 7-digit model number. It doesn't acknowledge the numbers I have tried. It doesn't have any ability to search for the model number based on the name of the laptop, or any other characteristics about it. It wants me to find my PC using their "find my PC" crap, which asks me generic questions about my desires and then tells me what Lenovo product to buy. Apparently since I'm a past customer and not a current or future customer (and probably never will be, after this experience), they hate me.

So I surveyed the web. It is well-known that the model number of the Lenovo Ideapad U-150 is model number 6909. Lenovo's website is the only resource that insists every Lenovo product has a 7-digit product number.

I call the question: Are Lenovo model numbers all 7-digit?

Lenovo: You've been out-voted.

Also, Lenovo: you suck.

This is an example of something PC manufacturers are very good at. I didn't even know I wanted a skinnier battery. Through lies and misrepresentations and untruths, they convinced me that such a thing existed (and therefore that I wanted it). Then through incompetence and bad design and idiocy, they convinced me that I can't have it (at least not from them). Now I'm mad at them for failing to give me something I didn't even know I wanted.