Will my new laptop AC power adapter work with my laptop, given these specs?
2014-07
NoCatharsis
My laptop's AC adapter went out last night and I bought a replacement today, but will not be able to test it until tonight or tomorrow.
My laptop is a Gateway P7801-U, but unfortunately Gateway does a very poor job of detailing their specs and no power requirements are given beyond the battery capacity.
The label on the old adapter says 19V @ 6.3A max. The new adapter I bought is this Lenmar 120W model with variable voltage setting. I read on the packaging that the current is only 5.5A when set at 19V though.
I'm a mechanical engineer and not an electrical engineer for a reason, and I have no idea what these numbers mean when it comes to plugging in my laptop. Could I run the system at this lower amperage? Do I want to? In other words, would I be able to turn the machine on at all, or even worse, damage it?
Blackbeagle
If you have the same voltage, but different amperage then the power supply could theoretically burn out faster. Basically the normal analogy is voltage is pressure. You have the same amount. Amperage is flow - the adapter isn't capable of delivering as much as the old one. This could cause the adapter to overheat as it would be running at higher percentages of its capacity versus the old one. The main issue is how much draw are you doing? Are you running the screen at full brightness, running lots of stuff off the USB ports, running heavy applications... Anything that brings your laptop up to max capacity will draw more power.
Linker3000
Blackbeagle raises good points about current and voltage. To check a bit further, I have had a look at what various suppliers are specifying for a third party replacement, and the current ratings I have found range from 4.9A to 5.5A - for example, this one on Amazon:
http://www.amazon.com/Replacement-Warranty-P-6831fx-P-6860fx-Computer/dp/B003E1RYWO
This is listed as:
Replacement Plug with 5 Year Warranty for Gateway Laptop Ac Adapter P-6825 P-6828h P-6829h P-6831fx P-6832 P-6836 P-6860fx P-7801 P-7801u P-7805u P-7805u Computer Power Battery Charger 90w
..and the power spec is as follows:
19V,90w ,4.74A
I found that particular model listed on various sites so I would suggest that your 120W (5.5A) unit will probably be fine.
Edit: More evidence:
Compatible 90W Gateway P-7801u FX AC Adapter. Replacement 19V 4.74A laptop AC Adapter is guaranteed to meet or exceed original Gateway P-7801u FX AC Adapter specifications.
Leftium
Lugging my X301 between work and home, I realized my laptop's accessories weigh more than the laptop itself!
I'm ordering a 2nd AC power adapter so I don't even have to carry one at all, but I may as well get the lightest one possible. My X301 came with a pretty svelt 65W power adapter, but can anyone suggest a lighter power adapter or confirm the weights I've found below?
mass vol dimensions W Model ---- ------- ----------- --- ------------------- 210g 149cm^3 108x46x30mm 65W Coolermaster [NA 65] 244g 189cm^3 140x75x18mm 65W ThermalTake [ADP65W0001] 260g 130cm^3 104x43x29mm 65W Lenovo (came with X301) 326g 198cm^3 145x76x18mm 95W Coolermaster [SNA 95] 330g 180cm^3 150x60x20mm 90W Kensington USB [K38030US]
Apple's 60W power adapter seems much smaller/lighter than the PC products listed above, so I think a better PC power adapter could exist. There are much smaller 45W "netbook" adapters, but are these too weak for my X301? I would not mind if it just meant the battery couldn't charge while the laptop was on, but I am afraid there will be worse consequences.
Also, I have decided to swap my Logitech Kinetik briefcase for a Tom Bihn Ristretto. Less protection, but much lighter, less bulky, and easier to carry. Any suggestions for better laptop cases/bags?
Leftium
I ended up getting the Coolermaster [NA 65].
- Despite the difference in spec'ed mass, I can barely tell the difference between the original Lenovo one that came with my laptop. The difference probably comes down to how manufacturers weigh them (with/without cord, etc)
- The only real differences are in the cables. The Coolermaster one comes with tips for multiple makes of laptops and they are angled at 90 degrees. I actually prefer the Lenovo unangled design: it fits more snugly and I feel it brushing my lap less.
- I was able to personally physically handle the other candidates, but they all felt heavier and bulkier.
Also the Ristretto bag is awesome. Not as much padding/room as my Kinetik, but sufficient. The design is much, much more comfortable to carry around and convenient to quickly access. I take the Ristretto on short commutes to work, and the Kinetik on longer trips (where I need to stow the laptop in an overhead bin, or something).