Thinkpads Forum

Dear T61-Users,

recently I discovered something strange with my T61 (T7100, 1.8 GHz). If I am just working with the power-supply (65W), the frequency doesn't go above 1.2 GHz. As soon as I connect the battery, it can be switched to 1.8 GHz (windows: maximum performance, Linux with the 'speed-applet') without problems.

Also if only the battery is connected (power supply disconnected) the laptop can work at 1.8 GHz.

I don't remember whether this behavior is present since the beginning or whether it started with a recent bios-update.

There seem to be some threads scattered about about the problem, but most http://forum.notebookreview.com/showthread.php?t=159365 only tested under windows, but I can confirm the problem under linux too.

Does anyone have an idea what could be the problem??

It's not a problem, it's a default setting for Intel Speedstep-equipped chips, and has been for years.

You'll never be able to run the machine at full speed without the battery being physically present, because in Intel's opinion you could possibly draw too much current if you were running at full speed without battery as a backup source of power.

On older machines, there was a workaround around this in Linux, but not on newer ones. There was never any workaround for Windows as far as I know.

Hope this helps.

Thank you very much for the information, I wasn't aware of this. My t40p didn't have the limitation, and the few threads I read didn't give any conclusive answer.

Thank you!

You're very welcome.

Now plug that battery in and enjoy your new ThinkPad...

you can use the 90 w power adapter if you want full clock frequency with no battery attached.

This is really interesting, I run my T61 without the battery, in order to extend the battery life. I hadn't realized that slows the machine down. I have been doing some long running computation tasks and was impressed at how cool the machine had stayed. I have the 65 watt adapter that came with it. I guess I will buy the 95 watt one, though maybe I'll use the 65 watt most of the time since I like the cool operation.

In fact, wow, it runs 2x as fast with the battery attached. What happens if I run it that way for a long time, does the battery get drained and then the machine slows back down?

Thinking about it more, I'm really annoyed that the T61 shipped with an adapter uncapable of running the computer at full speed. They charged me $100 extra for the T9300 cpu and then only let me use half of it? Sigh.

Yeah, I think I'm going to get a 90W one myself. I see the battery being cycled a few percent all the time and I know that can't be good for it's health, since I use it on AC 95% of the time.

Even a 90w adapter, with no battery installed, will NOT run the machine's CPU at full speed, not in Windows anyway.

not sure, ajkula66...

Sometime back there was a guy using X61 or X61t having a big argument with me and Mark_Lenovo regarding lenovo not supplying the correct adapter for his laptop. He showed extensive tests that without battery, the 65 w was incapable of supporting the CPU at full frequency by itself. However, he showed that by attaching the 90 w adapter he was getting full frequency on his Core 2 duo processor rather than the throttled speed with the 65 w. I am assuming with the T61 no battery with 65 w adapter this would be the same case..

But anyway it is not recommended to run your laptop with no battery, due to accidental plug detachment causing sudden power loss to the laptop.

The battery act as UPS, as long as one prevents regular small top up charges, having battery in the machine is not much of a detriment. In addition, long term battery storage should occur at 30-50 % battery level to prevent damage to the battery cell.

Any speedstep-equipped ThinkPad that I've tested over the last eight years has behaved in the same fashion...

There is a way, in certain Linux distros, of getting around this, and there was a discussion on this issue in the "R,A,G,Z" thread a while ago...

Pull out the battery out of ANY of your ThinkPads and test the speeds...you'll most likely get the same result, regardless of the AC adapter wattage.

Does anyone have a 90w adapter they can test with? Or if they are willing to lend me the adapter for a few days (I'll pay for all shipping) I'll test it. I was about to order a 90w adapter but don't want to do that unless it does the trick.

My T61 is sitting securely on my desk at work and the plug doesn't seem likely to fall out. It is in there pretty solid and the machine doesn't get bumped around much. This is unlike my A22p at home, which I use in bed and which the plug falls out of all the time. But the A22p battery is practically shot, so I'm ok with leaving it in. I don't want to mess up the ultra expensive 9 cell T61 battery by leaving it in the machine except during actual portable operation.

I have the 90W adapter at home that I can test with tonight.

phr wrote:Does anyone have a 90w adapter they can test with?

Yes, it doesn't make any difference.

Batteries are a consumable item with a laptop, IMO there's not really much point in getting overly worried about "wearing out" a battery!

Cheers,

Bill B.

These batteries are ridiculously expensive, something like 200 bucks for the 9 cell one. Why the heck should I be consuming such a "consumable" when the laptop is plugged into AC power? This is nuts.

Ok, I just tried it, 90W adapter, no battery, full speed is possible. It doesn't kick in at first of course, I had to start opening apps and stuff to get it , but it kicked right up to full speed once the demands went up.

Forgot to specify, this is Windows Vista Business x64, Intel t8100, and I have the nVidia NVS140 GPU and a 250GB 7200RPM hard drive.

CPU speed checked with CPUZ 1.47.

phr wrote:These batteries are ridiculously expensive, something like 200 bucks for the 9 cell one.

Ridiculously expensive compared to what? 60-70 gallons of petrol, or a similar number of Big Macs?

LiON batteries wear out whether you use them or not, so what is it you think you are actually saving by taking it out of your ThinkPad while its docked?

Cheers,

Bill B.

bill bolton wrote:

phr wrote:These batteries are ridiculously expensive, something like 200 bucks for the 9 cell one.

Ridiculously expensive compared to what? 60-70 gallons of petrol, or a similar number of Big Macs?

LiON batteries wear out whether you use them or not, so what is it you think you are actually saving by taking it out of your ThinkPad while its docked?

The batteries lose substantial amounts of capacity after a few dozen to a few hundred charge cycles. My X40 battery went from 100% to 50% in about a year despite my not using that machine very much. I took the battery out of my T61 when I saw from the power management log that the battery was dropping to 95% and recharging several times a day, i.e. hundreds of cycles in just a few months.

Really, it is just bad design if the computer can't run at full speed without power from the battery. That means if you want to do a very long compute-intensive task, the battery is eventually drained and the computation has to slow down. I use my T61 primarily as a desktop computer which I think is common with these larger laptops. So it is on AC power basically all the time. I mostly use it for low-intensity text editing (so I didn't notice the slowdown at first) but I occasionally run multi-day CPU-intensive database operations on it etc.

The expense of the battery is ridiculous compared to the very minimal value it provides 95% of the time the computer is in operation (on AC power), and compared with the computer itself once the computer is no longer a recent model. An A22p battery is also about $200 new but the whole A22p (I still use one every day) is worth less than that.

Wentworth, that's interesting about storing the battery at 30-50%, I had been storing it completely charged. There is no obvious way to get the computer to not charge the battery when the battery is attached to the computer.

[quote="schiesz"]Ok, I just tried it, 90W adapter, no battery, full speed is possible. It doesn't kick in at first of course, I had to start opening apps and stuff to get it , but it kicked right up to full speed once the demands went up.

Forgot to specify, this is Windows Vista Business x64, Intel t8100, and I have the nVidia NVS140 GPU and a 250GB 7200RPM hard drive.

CPU speed checked with CPUZ 1.47.[/quote]

Thanks!!! I guess I will order a 90W adapter. There's always Marketplace if it doesn't help.

phr wrote: There is no obvious way to get the computer to not charge the battery when the battery is attached to the computer.

You can set thresholds for when to charge in the power management app.

bill bolton wrote:

phr wrote:These batteries are ridiculously expensive, something like 200 bucks for the 9 cell one.

Ridiculously expensive compared to what? 60-70 gallons of petrol, or a similar number of Big Macs?

LiON batteries wear out whether you use them or not, so what is it you think you are actually saving by taking it out of your ThinkPad while its docked?

Cheers,

Bill B.

With all due respect Bill, while there's no arguing with the fact that the batteries are perishable by design (shame), not all of us can afford that much gas either. (Nor, necessarily a car for that matter!)

Yes, some of us are living beyond our means when it comes to owning executive armcandy like ThinkPads.

Whee! It looks like there's a 20% off sale for ac adapters at lenovo.com. I just ordered a 90w adapter for something like $47.20 plus tax and shipping. I emailed a gripe to the sales rep I bought my t61 through asking if I could upgrade the 65w adapter, but afterwards shrugged it off and ordered the 90w. So, one or the other adapter may end up in the marketplace forum soon. I'll test it when it arrives and post the results here.

phr wrote:Whee! It looks like there's a 20% off sale for ac adapters at lenovo.com. I just ordered a 90w adapter for something like $47.20 plus tax and shipping. I emailed a gripe to the sales rep I bought my t61 through asking if I could upgrade the 65w adapter, but afterwards shrugged it off and ordered the 90w. So, one or the other adapter may end up in the marketplace forum soon. I'll test it when it arrives and post the results here.

You may want to keep the 65W one as it is smaller which may be useful on a trip.

phr wrote:Whee! It looks like there's a 20% off sale for ac adapters at lenovo.com. I just ordered a 90w adapter for something like $47.20 plus tax and shipping. I emailed a gripe to the sales rep I bought my t61 through asking if I could upgrade the 65w adapter, but afterwards shrugged it off and ordered the 90w. So, one or the other adapter may end up in the marketplace forum soon. I'll test it when it arrives and post the results here.

You may want to keep the 65W one as it is smaller which may be useful on a trip.

phr wrote:Whee! It looks like there's a 20% off sale for ac adapters at lenovo.com. I just ordered a 90w adapter for something like $47.20 plus tax and shipping. I emailed a gripe to the sales rep I bought my t61 through asking if I could upgrade the 65w adapter, but afterwards shrugged it off and ordered the 90w. So, one or the other adapter may end up in the marketplace forum soon. I'll test it when it arrives and post the results here.

You may want to keep the 65W one as it is smaller which may be useful on a trip.

If you want to store your battery for a long time, then store it at 30-50% pretty much how Lenovo sends their new battery in. To get to this level is quite easy, run your laptop on battery to 30 -50 % then switch off your laptop, and take out the battery. Nothing to it.

I've received my 90W adapter and can confirm, the t61 sans battery runs at full speed with it under Ubuntu GNU/Linux. The 90W adapter is quite a bit larger and heavier than the 65W but I guess I don't care that much since I don't usually travel with this machine. If I were travelling with it more, Lenovo offers an expensive compact/lightweight 90W adapter and I suppose I'd get that one instead.

Thanks for the info everyone.

Wentworth wrote:Sometime back there was a guy using X61 or X61t having a big argument with me and Mark_Lenovo regarding lenovo not supplying the correct adapter for his laptop.

with all due respect, he argued with almost everyone involved in that thread, not just you and mark.

for others' benefit, here is a link to the original thread along with the accepted solution posted by mark.

Well thank you for reminding me Erik, i forgot to mention your name, next time i will sure to reference you for all my posts.