Buyer Beware! - Your power adapter may be cheating you! [ Edited ]

[Mark_Lenovo Administrator]

ibm,

You are, of course entitled to escalate you position, and I do respect your individual opinion.   You did some testing, and presented your findings to the community.  I've researched them with engineering and provided an official answer that we understand what you have noted, and that is actually a design point.  This is not a flaw, and not considered a defect under warranty.

As far as I'm concerned, this has been asked and answered.  

I imagine that there are plenty of possible scenarios in which products can be taken outside the expected usage scenarios and unique situations created.   To try to caveat all of those possibilities and offer advice and options within a shopping flow is just not practical and would unnecessarily complicate the experience to the detriment of all.  

You obviously are technically savvy, and I think there are many ways for you to contribute and receive positive recognition from the community.  I hope that you will explore some of those and continue to participate here.   

I do respect your point of view, but don't believe further debate on this matter is beneficial.

Mark

Message Edited by Mark_Lenovo on 05-23-2008 09:56 AM

[wojciech_czyz]

IBM - thank you very much for your post, I made sure that both in my work and at home I have 90W power supply connected. From now on I will use 65W only when travelling. Although I mostly have my battery connected, I use the 90W power supply to make sure that battery wont be used for buffer, and thus it´s life will have maximum length. In short, for those that are still not convinced by the "pi calculations" - try the performance graphs on your PC during normal usage. Anytime CPU load goes high on 65W, you have just stolen some energy from the battery that will eventually shorten it´s life. Its happening visibly when PC is booting up, you are loading applications (MS Office), scanning disk for viruses or defragmenting it, playing games, opening and browsing complex web pages (Web 2.0).

Personally, I also do support your point, I think Lenovo should state on their web pages that 65W power supply is light and travel-friendly, while may be too small if machine has to be used with full processor load or external devices and the battery is disconnected. It should be pointed out, that using 65W power supply and battery at the same time will shorter battery life by "stealing" battery power when power supply is not enough.

It is true that many users will not care about the battery life or maximum CPU clock, but there is a reason why Lenovo should state the full information to the users. In my opinion, if I state the exact CPU speed in MHz, I should also note conditions for this speed to be reached. I mean as soon as you get down to numbers, you have to be precise. Give the information and let users decide what configuration to buy.

Mark_lenovo - thank you for explaining the technical background why exactly 65W power supply might not be sufficient and how X61T power management works. Perfect candidate for the documentation in Support section on Lenovo website, will you agree?

Finally, for those that have only 65W - use the external powered USB hubs with its own power supply.

[thommango]

If you're not actually spending much time calculating pi, then you're probably using peak CPU for some small fraction of overall computing time.  Are you sure that's diminishing the lifespan of your battery?  I'm no expert, but given that batteries start to fail when they are not cycled through the charge/discharge process, I think it's equally possible that by stealing a bit of juice from the battery now and again, the 65w power supply is actually increasing the battery's lifespan.  My guess is that it simply doesn't make any difference at all.  But if you are correct in assuming that it reduces the battery lifespan, I would find that disconcerting. 

[wojciech_czyz]

Hello,

Please correct me if I am wrong. I should correct the statement written in red:

[...] I'm no expert, but given that batteries start to fail when they are not cycled through the charge/discharge process, I think it's equally possible that by stealing a bit of juice from the battery now and again, the 65w power supply is actually increasing the battery's lifespan.[...]

Li-ion batteries have limited number of charge cycles, any charging of battery count as a cycle here, because you are starting certain chemical process EVERY TIME you start charging battery. You have got around 400 cycles - exact count depends on battery type and your luck, as they are chemical devices not precise electronic counters. Apart from the number of cycles, battery also ages whether used or not, with maximum is 3-5 years. Finally, Li-Ion battery simply dies if it is left to discharge completely, internal electronic will switch it off as it is dangerous to charge it again.

So the red statement is invalid, as it is always better to leave (connected) battery alone without using it, this will postpone the moment it will loose it´s charge over time and drop below the threshold value to be recharged again. Only then the next charge cycle will be stolen.

Now I understand that another intention of the question is how much of the battery charge will be stolen and then how many cycles will we loose by backing up 65W power supply with battery. We can detect it ourselves, we have to use PC in normal conditions with 65W and see how fast battery charge will drop to 95%. Then do the same with 90W and compare the times. I am using 90W power supply since several days and still have 100%, who has got his battery recently completely loaded? What is your charge level? BTW - if I remember well, the Lenovo power manager Balanced power plan does not give 100% CPU speed even if overloaded, even on external power supply.

[amn]

You other people judging and testing the user 'ibm', you are very wrong. I am sitting here with exactly the same problem as him/her, and please do not give me advice how to run my T61.

[erik Community SuperMod]

---

amn wrote:

You other people judging and testing the user 'ibm', you are very wrong. I am sitting here with exactly the same problem as him/her, and please do not give me advice how to run my T61.

---

the obvious solution is to use your T61 with a battery as it was designed.

have you read this post earlier in this thread?

[amn]

Yes I did, and what does it have to do with anything?

My point is, the buyer should be made aware beforehand that if he removes the battery (it can be removed too) the CPU locks frequency at 1.2Ghz.

Caching in on 90W adapters afterwards is nothing short of greed backed up by false advertising. "Wow, now I have 2!". Did you know by the way that there are mile high piles of assorted adapters of various kinds at junk yards from U.S. to Singapore?

That solution you proposed is not a solution, if only because the Lenovo installed OpenSUSE Linux suffers from the same problem, and unfortunately for the owner and the battery there is no such thing in OpenSUSE Linux as Thinkpad Power Management, which has a set of nice features to prolong installed battery life by say charge thresholds etc. So, is this a solution then? No. It is more like an attempt to not only cache in on extra AC adapters but on batteries too. But if I am going to buy a expendable laptop plastic toy, I would buy some Korean stuff, not a Thinkpad. I thought Lenovo cared, i mean talking about business workstations and all.

Even if it is true about 65 watts not enough, then WHY SELL them with Thinkpads that cannot reach their advertised speeds? Or why there is no warning when opting for one to go with a Thinkpad? When you buy a car, do they, without your knowledge, install a 200hp engine and pair it with a awfully thin fuel cable, so you after a years use and careful suspicions at first find out that you only been using at most half of the engines power, and they explain it that that is the way the card was designed to go, but if you want all the power you originally opted for, you have to buy a thicker fuel cable. The explanation is fine, no doubts about it. But then, what is that thin cable doing in there to begin with?!

[georoid]

Well, this seems to be too late to reply, but I totally agree with ibm and amn's opinions.

I happened to check my cpu with Intel processor identification utility and found that my CPU runs at 1.19 GHz.

Well, I first thought that I may need to change my power options, but nothing changed.

Then, I tried the utility on my desktop and it showed the desktop cpu was running at its full speed.

So, I was googling if there is any other case like I found.

Here it is~!

ibm clearly mentioned the exactly same problem. Well, some may say why these guys don’t use battery but use 65W adapter only?

But it is my preference. Like some others, I would like to preserve my battery. As I have used several different laptops, based on my experiences, I think using battery in the laptop all the time does shorten the battery life.

Anyway, my point is that Lenovo should have mentioned about this issue in the manual, specification, or flyer.

Some may like to use the laptop longer, some may want to use it with full speed, and the other may want lighter battery or adapter. I believe that depends on who is using it. However, as there are specifications for parts such as adapters, cpus, rams, network cards, etc., when I purchased a laptop, I had an expectation that my laptop would run at  xx speed, and my battery would last for xx hours, and my laptop takes xx hours to charge. We got the information from the specifications, flyers, and manuals. If anything is different from the advertisement, it also should be noted.

If I knew it about the cpu speed issues with power sources, I must have had 90W adapter too.

It's like advertising that a SUV car runs 35 mpg without saying when it is on highway. But they do say it even if it is very small and on the corner of a flyer.

So,  at least from now on, Lenovo should put that info something like “CPU runs 74% with 65W adapter, 100% with 90W adapter, and 100% with battery”

[Aerith]

Admittedly, I don't personally own a Lenovo notebook (though I will as soon as the bloody UPS exception clears), but I've owned enough notebooks and desktops to know a fair share.

When I read the start of the thread, the first thought that came to mind is that the notebook CPU is being underclocked when the 65W adapter is plugged in. As Mark_Lenovo has stated, I correctly assumed it to be an intentional 'feature' of Lenovo's.

The idea, in my opinion, is that a notebook is designed to be used with a battery attached. I would imagine that when most people plug their notebooks into an outlet, they're going to keep the battery plugged in as well, REGARDLESS of whether it is charged or not. The main reason is, as another user has stated, that the battery prevents against data loss by acting as a UPS. A second reason would be to facilitate mobility.

Thus, I would completely understand why Lenovo chose to err on the safe side and underclock the system a bit when running it off the 65W adapter sans battery. Sounds totally reasonable to me.

Now. If you'd like to resolve your 'problem' without having to attach the battery, there must be a number of ways to do so. There are a couple programs that allow one to under/overclock various components of the system:

In the case of the CPU, there is RMClock and Notebook Hardware Control. Depending on the CPU and motherboard you have, you might be able to change more or less settings. These should allow you to set up profiles that override the power settings that the notebook uses inherently.

However, you do so at your own risk. For one, you risk immediate data loss. Aside from that, you risk damaging your system and voiding the warranty by forcibly under/over volting the CPU/FSB. Your best bet, however, would be, in my opinion, to just plug in the battery and buy another one 2-3 years down the line when the current one becomes overly worn down. After all, if you already paid over $1K for a device, a bit more for a battery shouldn't be that much, especially given that one can get 'em from OEMs if you don't want to shell out the cash to get them directly from Lenovo.

[jyeah]

I know it has been quite a long time since the last post, but I just got an X201T and observed the same issue.

At the same time from testing, I believe this is working as intended for power hungry machines, but not the case for laptops that use the LV and ULV versions of the CPU.

This is because when the Intel SpeedStep Technology option in BIOS is turned off (disabled), the CPU is no longer bottlenecked and runs at full speed. So does that mean the laptop is running in a safe and stable condition? If it is, then by default, that means when Intel SpeedStep is enabled, we should still be able to run the CPU without any bottlenecks without the battery plugged in (since when it's disabled, we could). If not, that means this is definitely a design flaw. Since Intel SpeedStep Technology is merely a throttling technology, meant to save power ("Enhanced Intel SpeedStep® Technology is an advanced means of enabling very high performance while also meeting the power-conservation needs of mobile systems," quoted from Intel). It was not meant to ensure the system does not draw too much power for the power adapter to handle (it was designed to save battery life). That is not by design at least not from Intel's standpoint.

So will we be getting a fix to this issue? Or escalated to the engineering department again?