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Laptop Power supply (AC Adapter)

Last response: in Components
a b D Laptop
March 14, 2013 2:36:38 PM

My Y570 comes with a 90W ac adapter. The CPU uses 45W and the GPU also uses 45W. Wouldn't this leave no power for the rest of the components?

More about : laptop power supply adapter

a b ) Power supply
March 15, 2013 2:02:56 PM

The computer/laptop has a way to amplify the energy more once it is in the machine.
a b ) Power supply
March 15, 2013 6:56:47 PM

Your laptop is not magical. It cannot create power out of nothing. That power brick converts the AC power at your wall into DC power. This is usually 20V DC power, that then gets converted again to the various voltages your laptop needs.

Volts x amps = watts. 20V x 4.5A = 90W. The draw at the wall will be more, because the brick is not so efficient. So It might need 1.4A of 115V power... and the difference is lost to heat. You notice how hot your brick gets while the laptop is charging, I'm sure.

Those wattage numbers you gave are not even the maximum draw of those items... it's what they are rated for thermally.

However, none of that actually happens continuously. While your power supply is steadily supplying maximum power until the battery is charged, the computer is using varying amounts of power. So, it can draw more than it's getting because it has a reserve.

If you do try to use more power than you have available, the laptop has ways to limit itself. It won't run at full speed if it doesn't have the available power.
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March 31, 2013 5:55:26 AM

i think its better to use a more powerfull adapter, like the 150w

Like this the adapter will not break down so easy. I have also an asus laptop wich was provided with a 90W power ac laptop adapter. It was getting very hot all the time and since i ordered the 150w power ac adapter it charges way more fast the battery and the adapter does not get so hot. I use the adapter also for my alienware and packard bell laptops.
a b D Laptop
May 20, 2013 9:26:53 AM

chargerbuy said:
the 90W adapter will burn down your laptop. You shold use compatible adapter for the laptop.

The 90w is what it came with
a b ) Power supply
May 20, 2013 11:48:50 PM

I wonder what might motivate someone named "chargerbuy" to make false claims about chargers? Oh, wait, no I don't.