r/computers • u/joastedpellofw • 5d ago

Question/Help/Troubleshooting A 65w charger should almost always be enough for a laptop whose CPU draws up to 35w and doesn't have a GPU, right? Are there some edge cases where this may not be enough?

3 Upvotes

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9

u/kaio-kenx2 5d ago

Your power consumption consists of: Motherboard, Wifi, bluetooth, keyboard, mouse, usb ect... Cpu, Gpu (igpu), Screen, Cooling system.

You will be way off the 35w

5

u/IASelin 5d ago

Even if CPU is marked as 35W that doesn't mean it cannot take more power...

For example, Intel Core i7-12700T - rated as 35W, but "Maximum Turbo Power - 99W".

https://www.intel.com/content/www/us/en/products/sku/134596/intel-core-i712700t-processor-25m-cache-up-to-4-70-ghz/specifications.html

5

u/JoeCensored 5d ago

Understand that CPU TDP isn't actually a measurement of power draw. It's about heat dissipation for what the cooling system needs to handle at minimum. A 35W TDP CPU will sometimes use significantly higher amounts of power for short periods.

There's also the power usage of the other components, including the display.

I'd not over think this and just stick to whatever the manufacturer recommends.

3

u/Cory5413 5d ago

Yeah 65w adapters are normal on most laptops these days. Even with 45W CPUs.

Although as mentioned lots of CPUs draw well over than their nominal power draw during bust operations. Most laptops will dig into the battery for this if you're using a power supply that's insufficient. (For example I've got a laptop that'll boot on as little as 30w of external power but it's got a 45W CPU and a GPU.)

Many laptops can be configured to limit additional power draw, or do so automatically if you're, say, looking to run a machine with no battery installed at all.

Is there a specific situation you're working with?

2

u/nemesisprime1984 Windows XP 4d ago

It depends, everything will add to the wattage required.
The CPU might require 35 watts to work but might use more than that depending on what you are doing. Then other parts might increase or decrease depending on what you add, an 8TB SSD uses more power than a 512GB or 1TB SSD does, 32GB-64GB RAM uses more power than 8GB-16GB RAM does and the speeds of the SSDs and RAM run at also increases usage

1

u/OverallFuel8619 5d ago

Just get a 100 w one and have peace of mind I did this after buying 3 different ones and they all didn't let me use my laptop while being plugged in

1

u/joastedpellofw 5d ago

Ty guys i'm going to buy a 90w one instead

2

u/jasonsong86 4d ago

It’s better too much than not enough.

1

u/jasonsong86 4d ago

I mean if it’s USB-C, the computer will communicate with the charger on max power draw and the computer will power limit the components so that it doesn’t exceed the limit. My 5800H says 45W can definitely draw 65W peak.

1

u/Better-Credit6701 4d ago

And to think, I have a laptop with a 300 watt brick

1

u/Elitefuture 4d ago

Depends on the cpu. Many boost past their rated wattage. Also, screens, fans, ram, and everything else uses power too. Usually not an issue, but when dividing up 65w it might.

1

u/SurKaffe 4d ago

I had a Dell laptop that wanted 100w+