E1505 DC (auto/air) power adapter ??

the E1505/6400 uses a 65-watt AC adapter.

http://us.kensington.com/html/10450.html this one is very small and makes 70 watts.

My E1505 came with a 65-Watt DF263 AC power adapter made for Dell by LiteOn. When I go looking for an additional adapter I find Dell tells me I need a 90-Watt CF820 adapter for $49.95. The closest I can find to what I have is a 65-Watt PC531 adapter compatible with Dell™ Inspiron™ 6000/700m/710m Notebooks for $29.95.

I was wondering how much power my machine actually draws. So I hooked it up to my "Kill A Watt" power meter. I found that while turned off and recharging the battery it draws about 46 watts. When it's running and charging the battery it draws up to 67 watts. I tried running a 3DMARK05 benchmark to see what would happen and the power draw dropped to about 57 watts. I think it gave up on charging the battery while running the X1400 in 3D graphics.

I tried again after removing the battery. At the desktop with the screen at max brightness it draws 27-30 watts. Turning the screen brightness all the way down saves about 5 watts. When I tried 3DMARK05 again, it drew about 55 watts, just a little shy of when the battery was in. So I would conclude that my 65-Watt adapter can't charge the battery and run 3D graphics at the same time. I have a 85Whr battery, by the way.

I find it strange that Dell would sell me my E1505 with a 65-Watt adapter when they seem to only recommend using a 90-Watt adapter. In both the AC and Auto/Air adapters only the 90-Watt model is listed as being compatible with the E1505/6400. I suppose with one of those you might actually be able to charge your battery while playing 3D games.

Back to the original question: I think you may be really asking about amperage. If you're going to draw 66 watts from a 12 volt source, you're going to need 5.5 amps of current. The formula you may have been trying to remember is watts = amps x volts. Since my car's lighter socket is on a 15 amp fuse I wouldn't think there would be any problem drawing the power you'd need.

precisely.

as long as it supplies at least 65 watts and has a tip that fits the computer you want to use it with, you'll be just fine.

edit: now that i looked at your link, you're looking at something entirely different. that is a plug-in inverter, but yes, that will work provided you use the AC adapter that came with your computer.

If you're not needing to charge your Laptop on a airliner don't waste your money on an Auto/air adapter. I use a 150W Inverter I bought for $30 in my truck. Works just as good as an Auto/air adapter and is CHEAP. You can also use the inverter for powering more than just your Laptop.

any wal-mart should have a few to choose from, like MrEvil said, you should be able to find one that's more than 150w for less than $50, and usually the higher-wattage inverters have more than one plug.

http://accessories.us.dell.com/sna/p...9&sku=310-4804

FWIW: Above linked would be better to use than an inverter/adapter combo...

Better in what way, weight? The advantage of a generic inverter would be cost and ability to use it with other products.

I note Dell doesn't say that adapter is compatible with a E1505/6400, but I suspect it would work just as well as the 65 watt AC adapter they send with the E1505.

Nothing short of a true sine wave inverter produces a clean sine wave suitable for sensitive electronics like notebooks.
The cheap square wave inverters linked to in this thread are exactly that...cheap and not suitable for powering notebooks.

sorry to butt in on this thread, but i bought an inverter from walmart and it the power light doesnt come on when i turn it on. So I'm wondering what are the possible problems that it's not working.

maybe it's the fuse?

Oh poppycock, I've used a $30 Vector Inverter on my Inspiron 8200 on a couple 11 hour trips and the Laptop did just fine. No fried power bricks, no fried Laptop. According to Vector, they use a modified Sine wave, I'm guessing it's a nice way of saying that it's a mostly square wave. Then again, my F250 is also a Diesel whose electrical system has a near constant voltage.

i'm interested in getting an auto adapter. what's the cheapest one that will charge a e1505 w/o destroying anything?