65 Watt or 90 watt adapter for ThinkPad laptop?

[lenojustin]

Hello,

I am about to buy a Lenovo ThinkPad.
Its a T520, i7 2640M, 15. inch display, SSD, 4 GB RAM

I am given an option of 65 W or a 90 W adapter. Both are of same cost.

Please advise which to get?

My particular needs:

1. I intend to take out my Li ion battery and keep it away as my laptop is always connected to the power cord.
2. Also where I live it is very very hot for 9 months of the year. Like perpetually 90 degrees.
3. Price of both is same

Thanks a lot
Justin

 

[abekl]

you asked the same question on Toms.

 

[LumbergTech]

You need to go to the manufacturers website and determine the normal one. If you get the wrong one, your PC may run slower. My girlfriends Vostro 1500 can run on a 90 or a 65 watt, but the 65 watt literally slows down the PC.

 

[lenojustin]

Lenovo is offering both the 65 W and the 90 W chargers for the laptop. They are also asking for no additional cost. So I assume that both are compatible... only question is which is right for my need. I never intend to do hardcore multi tasking or power and CPU intensive tasks like video editing etc. I just use for business purpose and it is very hot where I live.

 

[rsutoratosu]

I have both.. 65w is smaller, good for travel, 90w is larger..

http://forum.thinkpads.com/viewtopic.php?t=66692

Also some discussions..

90w charges faster but ymmv, some says li-ion likes slow charge = 65w chargers.

I didn't see a difference between the two in term of performance.. I only use the 65 to travel.. smaller and lighter

 

[lenojustin]

Thanks a lot for the reply!

 

[fffblackmage]

With today's technology, I'd bet your new laptop uses way less power than my 4-year-old laptop. You should be perfectly fine with the 65W adapter.

You need to go to the manufacturers website and determine the normal one. If you get the wrong one, your PC may run slower. My girlfriends Vostro 1500 can run on a 90 or a 65 watt, but the 65 watt literally slows down the PC.

I would guess that happens because you're powering a laptop and trying the charge the battery at the same time. Seems like the priority is on charging the battery first before powering the laptop though.

 

[kevinsbane]

There is an issue with certain thinkpads where the use of the 65 watt adapter without a battery is insufficient to power your laptop at heavy loads. It will downclock itself under those conditions. This is a known issue, and can be referenced here. I do not know whether it applies to the T520.

If you plan on doing a lot of travelling, use the 65 watter. If you are primarily at home, get the 90 watter. Seeing as how you say you will "always" be connected on power, I would say go with the 90 watter. It will ensure full performance of your laptop if you do not plug the battery in.

Personally, I use the 65 watter with my x220; except that I do not take the charger with me anywhere. Battery life on the X220 (6 cell) is sufficient for ~6 hours of on time at web surfing/spreadsheet activity levels. The T520 doesn't quite have the battery life of an x220, but you should get 4-5 hours easily. Get the 90 watter, leave it at home when you go on the road.

 

[lenojustin]

Thank you very much for the replies guys!

 

[Joseph F]

I've got a 65W 20V Lenovo charger you can have for free. (Plus shipping)
I used it with a Thinkpad R60.

 

[lenojustin]

Thanks a lot Joseph! I will defintely take you up on the offer if i need the 65 w adapter! Kind Regards Justin