according to the tabook and the lenovo web page. I thought Sandy Bridge's 32nm chips were supposed to be more power efficient than the previous generation? Don't want the giant power brick...

Sandy Bridge has the pretty much the same TDP as Arrandale/Clarksfield: 18W for ULV, 25 for LV, 35 for normal-voltage dual-core, 45 for quad-core, and 55 for 'extreme' quad-core.
The new graphics chips may be more power-hungry than previous generation.

EDIT: SB may be more 'efficient' in terms of reducing its performance & power use when idle; the AC adapter needs to be able to handle the maximum power draw including charging the battery.

the 135 watt power adapter is already pretty large, i can't imagine the size of the 170 watt...

Its this monstrosity from the w700 line: http://hothardware.com/image_popup.aspx?image=big_3.jpg&articleid=1223&t=a

Are they serious? Why can't they make it less thicker, while sacrificing real estate. I prefer to handle a canvas than a brick.

Does that thing come with it's own case on wheels?

These can be a great self defense weapon.... if attacked wield these power adapter as a morning star...

Just checked on the Lenovo site, and it seems that this is a new Adapter, not the one of the 700 series. About same size and weight as the old 135W adapter.

Can not wait to get one of these machines ...

Hmm interesting. On the page for the 135W adapter http://www-307.ibm.com/pc/support/site.wss/document.do?lndocid=MIGR-74503 they say that the W520 needs a 170W adapter and link to the W700 adapter http://www-307.ibm.com/pc/support/site.wss/document.do?lndocid=MIGR-70684. But then there is also a separate 170W ac adapter page for the W520 http://www-307.ibm.com/pc/support/site.wss/MIGR-76762.html. Confusion reigns, as usual...

If the dimensions are correct, then the size of the 170W W520 AC adapter is somewhere in-between the 135W and the W700 170W adapter:

* Approximate height: 35.0 mm (1.38 in)
* Approximate width: 80.0 mm (3.15in)
* Approximate length: 170.0 mm (6.69 in)
* Weight: 770 g (1.70 lb)\

This is retarded. They should give the option to use the 90W - it should be fine for most uses.

you can use the old 135 watt adapter with the w520, but not the new 170 watt adapter with any other system. 90 watt would probably not be able to run the system at anything close to full performance, so they are just covering their a$$es on that one.

And they're selling a special auto adapter that hooks directly to your vehicle's alternator. Kidding of course, but I'm not seeing any auto/air adapter for this one on Lenovo's site. Well, it looks like it's the same power connector as always, so hopefully it won't melt my Targus adapter!

don't try to use a cigarette lighter to ac adpter with this - all I've seen max at about 85watts peak It will become one with the car if you try to use it for the 170 watt adapter.

No doubt!

I do have an old APC inverter somewhere in the van that I haven't used since replacing the an old Dell Inspiron 8600 (Pentium M) with the T61p (Core 2 Duo)... it wasn't able to provide enough output to keep the Thinkpad from oscillating between power states (probably a 75W inverter).

My current ac/auto/air adapter (not an inverter) is rated for 90W, but it sounds like that's nowhere close for the W520. Can't find anything more than 100W online in this sort of thing. I'll probably try the 90W adapter at least once just to see if it can do anything (other than overheat).

I am seeing one invert that claims 200W while still connecting via a power socket rather than hard-wired, but the reviews from anyone trying a substantial load indicates that the inverter isn't really up to it.

So, let's see... 170W at 20VDC is 8.5A; just over 14A at 12V. 10 gauge wire probably indicates something that should be direct connected. CarNetix makes a DC/DC power supply for car PCs that can do 150W at 20V. But if you're going to bolt something into the car, it would probably make more sense to go with a more generally useful RV-style inverter and bring along the brick.

I can see why they aren't offering an auto/air adapter!

At least the battery life seems to be pretty good on these. I suppose I would probably go with the slice battery before trying to set my car on fire... though recharging that would be a bit of a pain since I'd have to leave the computer undocked or buy the external charger.

Charging batteries would be faster with the 170W adapter. The W510 with the 135W adapter takes too long to charge up (the system just draws so much power with little wattage left for charging the battery simultaneously).

What I really would like is a slice battery with the power adapter built in, something that integrate well with the laptop, physically (easier to pack & go). This, I think, would be a rather slick design as you only need one 2-pin power cable plug into the slice battery (the current design of power cable-->brick-->powercable-->laptop looks rather clumsy to me). The problem though, would be the temperature from the power adapter might make the battery unstable (and with shorter life) due to the close proximity (and possibly with other issues as well, such as shielding and interference).

It would be a real innovation on Lenovo's part if they can come up with a AC->DC voltage converter with near-zero-energy-lost. Current designs just generates too much heat, and is not exactly what I would call "efficient".

Also, I want some carbon nanotube power cells!

Added: Sometimes, I feel that laptop manufacturers are not innovating anything at all. All they seem to do is slapping OEM hardware together, add a system board, BIOS logic...and that's it. Years after years, we're still carrying a brick-like power adapter...WHY? The whole thing just doesn't say "portability" (yes, it has to be plugged in, I understand, but doesn't it have to be designed with portability in mind for the laptop market?).

Good Grief!

You do not need to use the big charger if you do not want to do so. I use my travel thin 90W and it works fine with my W510 and W520. You get a little warning message but your laptop runs just the same. The W520 charger is the same as the W510 unit. It is big but the W5XX is no netbook! You people are complaining about nothing!

For my part, I hope I came across only as concerned, not complaining. I do appreciate your sharing your experience with the 90W adapter and hope I have similar success. You may have noticed that the tabook does not list anything other than the new 170W adapter as compatible with the W520 while the 135W adapter is listed for the W510.

IMO, there's nothing wrong with adapter bricks.

As for the whole wattage thing, here are the TDP's for the CPU/GPU:
Quadro 1000M: 45W
Quadro 2000M: 55W
Dual-core SB: 35W
Quad-core SB: 45W

Kinda pushing it if you expect to charge the battery on a 90W adapter, especially if you consider all the other components. Actually, I'm fairly sure it'll draw power from the battery when under load, so instead of charging your battery, you're actually draining it while under load.

The Lenovo Canada online ordering site for the W520 says it's comes with a "170W Slim AC Adapter - North America, Latin America (2pin)". I can't find any specifications for this "slim" adapter but a Lenovo rep told me via online Chat that it is smaller than the standard 170W adapter that comes with the US version. He didn't have any specs for it though so I don't know if he was just guessing.

http://shop.lenovo.com/SEUILibrary/controller/e/webca/LenovoPortal/en_CA/builder.workflow:Enter?sb=%3A00000025%3A00002D97%3A&smid=F074AD2090D2080CC2F15C0005A1FD1F

Scroll down to the Power Cord section.

I think thats a practical joke of the canadian Lenovo web page maintainer, especially considering that there is no "full-size" 170W adapter to choose from

LoL...Complaining/whining about other people complaining/whining....

Can I use one of my old 90W T61p adapters to charge the battery of my new W520 (currently on order) while it's powered down? I have a spare 90W adapter kicking around in my car in a box with my inverter, it'd be convenient to keep that arrangement for the (rare, short) times I use my ThinkPad from the car.

Just trying to make sure here, everything I've seen so far in this thread indicates that I can.

@kb3edk -- I will definitely be finding out what you can do with a 90W adapter on a W520 soon after mine arrives. I spend a couple hours a week working in our van while my child is at some activity or other. I do *not* expect to do video rendering on 90W, but with the Quadra 2000M shut down and maybe the 2820QM can turn off unneeded cores or at least run less than full-out, with the LED backlight, and with the OS on a mSATA, I'd think I could get enough power from a 90W DC-DC adapter for coding/text editing. I don't see any way to power 170W from the car, at least not with the engine off.

If you don't find out for yourself first and if I've forgotten to post what happens (yeah, I'll take photos if I melt anything!), feel free to PM me.

My 90Watt charges the battery just fine. My slim 90watt even charges while I have my W520 powered up so there is power to spare to charge the battery under normal load.

So you've got the W520 already? Can you post the specs and maybe a 3DMark06 score?

Don't have my W520 yet (ordered early on the 29th; they say it should ship the 8th), but the dock did ship out so I have one of the new 170W adapters sitting on the desk in front of me along with the 90W one from my T61p.

It's 735 grams (1lb 10oz.) vs 387g (13-5/8oz). That's 1.899x the mass for 1.889x the power. Remarkable coincidence how those two ratios are so close. (Weighed with USA cord.)

They lengthened the velcro strap just a little which was necessary; there's only just enough overlap with that change to secure the cables.

It also has squishy rubber feet on the bottom where the 90W adapter has just plastic dimples.

The strain relief is larger (to be in proportion to the adapter?), but the cable itself is the same diameter.

I can still easily fit the new adapter in the mesh side pockets of the ubiquitous Wenger/SwissGear backpack I use, so that's one advantage of the "brick" design vs something broader and flatter.

Finally had a chance to see what happened with the W520 and a 90W Targus universal travel adapter running from the cigarette lighter.

Executive summary: nothing.

System will not boot from that power source alone. Briefly lights the power light; ThinkLight and mute button blink; disk light turns on and right back off; won't even go to POST and shuts itself back off.

If the power adapter and the battery are both connected, the following appears from the BIOS...
Once booted, the system appears to be running on battery, but using the "Plugged in" settings for whatever power scheme. The battery tab of the Lenovo Power Manager application includes a note: "This AC adapter may not provide enough power to your ThinkPad. Please reconnect the proper AC adapter." A dialog box appeared with the same warning and a link to a page for ordering batteries and power supplies (that doesn't yet include the W520).

With this adapter plugged in, it calculated the time remaining at 6:21. When I removed the power adapter, I'm guessing the battery settings kicked in; it jumped up to 7:44. When I selected the Maximum Battery Life plan, the time calculated was 9:24 --- but it might have been higher; I had to turn the brightness up to see the screen (sun shining in the front seat of our van.) The battery was reporting 100% charge.

I'd suggest that another way to say this is to "Be sure to use a DC to AC inverter capable of handling the 185 watt power brick". And yes, they are readily available from a variety of sources. I own this one http://www.radioshack.com/product/index.jsp?productId=3896267 from Radio Shack, although I don't highly recommend it. I'd also recommend using a small surge protector.

Yes, a 65W baby brick for the T61 will charge the battery in the W520 while the computer is off. Did mine overnight last night.

So if you want to do all your charging while you sleep and use the computer on battery only during the day you can travel with the smaller brick.

If however you need to use the computer all day and expect to do it plugged in, better take the big brick.

I actually only need the computer on 30-40% of the time during the day while I travel so the baby brick will work fine. Battery during the day and powered off and charging at night.

Perry

That's for that info; my battery is still at 84% on its first cycle, so I hadn't had a chance to try