Lenovo W510 Review: Powerbrick Swapping !

Notebookreview.com's review confidence and integrity has been lowered a notch....

I cannot believe that the review spend effort swapping the power brick with a lower wattage one. It's not clear witch power supply was used for the performance tests. It's also quite possible that the original power supply had improved filtering, and using a lesser one could have damaged the computer. Some of the readers may not have the technical ability to determine whether or not an adapter swap should or should not be done, and which swap may or may not present a safety/fire hazard. Not only does the power supply voltage have to be correct, but it must have sufficient current to safely operate the computer without blowing the internal fuse/circuit breaker--or over-heat.

Please, issue the reviewer a written warning, or something...and put a disclaimer in the article before some fool plays adapter swappy, and starts their house on fire. While the power supply would usually die first, do not taunt lithium. It's a quad-core laptop, with a dedicated video chip; it's going to take some power. If the reviewer wants to be playing power-supply games with $2000 computer, just send the damn thing to me, instead.

Another product, misused: http://www.youtube.com/watch?v=Gb6iCyYULxY

 

Well...

I was clear to me...

Performance with 135 power brick:
Wprime: 12 sec
PCmark: 7180

Performance with lower wattage powerbrick:
"wPrime in this mode took more than 70 seconds to complete and the PCMark05 returned a score of 2,000."

 

I guess this was no case for diplomacy; the tests were invalid as well. Send me the computer.

 

The W510 should have power management system that detects the lower power input, as it knows which adapter are plugged in (check your Power manager, it tells you which adapter is been used). It should be smart enough to downgrade the performance as to prevent overloading the power adapters.

However, it is wise not to use the lower power spec adapters in these machines, just in case accidents happen.

 

Obviously the W510 does downgrade the performance if it is paired with an insufficient power supply. Otherwise it would certainly crash as soon as the AC adapter can't maintain the necessary voltage.

I guess the lawyers made sure that this wouldn't be advertised as such.

 

You would think that, on a lower powered adapter, the laptop could pull power from the battery as needed to maintain full performance. At least, that's what the fruit company computers used to do.

 

If it would really damage the W510 or the 90W AC adapter, Lenovo would have made it impossible to plug in a lower wattage adapter (use a different plug shape or something). But Lenovo did not, and instead chose to lock the CPU/GPU to a lower power state when an insufficient power adapter is connected.

So, if you use a 90W standard Thinkpad AC adapter in the W510, it won't damage either the machine or the power adapter, although performance will be reduced and with a greater load on the lower-wattage AC adapter, the power brick will likely run hotter.

That excerpt of the NBR review of the W510 addresses a big concern of many Thinkpad users, because up to this point, all the _60, _61, _x00 series Thinkpads could all run on the 90W power adapter, and many Thinkpad owners have several spares of these adapters lying around - if they buy a new W510, they would be interested to know whether or not their old power adapter would work, and what consequences there would be.

In short, it's hardly as dangerous as you say it is, and just the fact that the W510 downclocks on the 90W adapter shows that Lenovo took this change into consideration.

 

Why were they invalid? I just can't understand your point.

 

It's not dangerous at all. In fact, I applaud the reviewer for checking it out with a smaller power adapter (presumably a 90 watt model). ThinkPad users benefit from years of consistent design and have many adapters lying around. It's only natural that a user would try using a spare adapter and it's important to know that performance will be severely compromised if they try using a smaller power brick.

If this was potentially dangerous Lenovo would have created a design constraint like when they switched from 16V to 20V adapters a few years back.

 

w700 used a distinctive adapter...

 

When you put 87-octane gasoline into a sports car that requires 93-octane gasoline. The computer would retard the timing and therefore affect the performance of the car. Are you going to give the manufacturer a bad review because you've been using 87-octane gasoline for your last few cars?

 

That's not what the review did at all. The review clearly indicated what the results were using the 135W adapter and what they were using the 90W adapter (which resulted in greatly diminished performance).

 

Here are some benchmarks with different power bricks:
http://forum.thinkpads.com/viewtopic.php?f=48&t=84627&start=30

 

Out of curiosity, where do you see that? I just looked in Power Manager 3.11a on my T510 and I can't see that information anywhere. There's a ton of info on the battery and it's current condition, but I could see no indication of which power adapter was connected....?

 

Above the battery maintenance button (for me atleast).

 

Yep, but note that you have to have your battery plugged in to see which adapter is plugged in. At the moment, that box is greyed out for me because I don't have my battery in my T500.

 

Not necessarily, sometimes you'd need to reflash the ECU for tigher or looser timings.

 

Hot-damn you're right! I was looking in the details section below the Battery Maintenance button, and I never noticed it in the little blurb above the button. Thanks for the tip! I guess it can deduce which adapter is plugged in by examining the incoming current and/or the rate at which the battery is charging.

 

I think you need to be careful with what you are saying if you have never in fact used this laptop with both power supplies. I am not some kid playing with his first notebook. I am not some stupid youngster smashing a WD40 bottle with a stick. If you want to insult me please at least do some research to understand my electronics background or my participation on this forum. I have been modifying laptops since my dad brought home my first Compaq Portable III and worked as a electronics tech up through college until I picked up this job here at NBR.

Both power supplies use the same Lenovo 20V plug (W700 had the beefier brick has a smaller and unique plug) which has been around forever and fully supported with all ThinkPad models. Lenovo and Dell (HP perhaps.. not sure) have been sticking with the same power adapters for many generations now for backwards compatibility. The notebook also knows which brick is currently plugged in through the middle pin which contains a resistor of unique value to identify itself. The charging circuit uses that value and adjusts the amount of power it is drawing. Almost all business notebooks and high-end consumer notebooks have this ability. Use a 65w power brick on a ThinkPad (or Dell) designed for a 90w and it lowers the charging Delta to the limit of the adapter. It doesnt try to draw a 90w load from the smaller brick. Same goes for the W510.

With that said upon powering on the notebook it immediately knew the non-135w brick was being used. No damage, just a statement that the notebook was being lowered into a low-power mode for the duration of that adapter being used. With the system charging from a dead battery AND being stressed it wasn't drawing more than 60W through the adapter measured at the wall. It forced the notebook into a mode that was slower than running off battery in max battery mode. That was the entire point if discussing it in the review, nothing more, end of discussion.

It was for the people who might have owned as many ThinkPads as I have. Some of us have collected a vast assortment of 65w, 90w, and 90w slim adapters over the years that continue to work just fine for use at home, in the car, at work, or on an airplane. The primary test was to see if it would work with the 90W AC/DC adapter that works in your car or on an airplane, obviously it didnt.

 

Plugging in a lower voltage power adapter will not hurt the Thinkpad. With Lenovo's at least the computer automagially knows what the voltage is and compensates accordingly. As for your "improved filtering" theory, considering that both the 90W and the 130W adapters used were from the same generation of chargers, they would both have the same filtering now wouldn't they.

So, basically, swapping a 130W Lenovo Charger with a 90W Lenovo Charger ain't gonna do crap.


Thank you, and goodnight.

 

i always thought the voltage is constant from the adapter, only the electric current varies according to the amount of power needed by the laptop?

 

you clearly don't know what you're talking about

 

Bingo!

Same thing applies to those desktops that come with 1k PSUs. It doesnt mean it will always draw that much.

I wouldn't comment on things if you dont understand what you are talking about. That comment was actually true for any modern fuel injected car. Any car worth its salt will have a knock sensor or two looped with the electronic ignition. If knock is detected it scales back the timing. Even my turbocharged high compression GTI did this. Outside of a few sportbikes or supercars basically anything designed to run gasoline is compatible with 87 octane fuel... but some cars will under-perform on it.

 

(took this image from a post on thinkpads.com)



Dell and Lenovo both use the same plug layout. The middle pin is the sensor pin to identify the brick to the computer so it can modify its charging profile. Basically its a resistor connected to ground.

 

Wow that is really cool! I didn't realize that. Learn something new every day, eh?