Laptop Charger Question..

spideypunk

Hi all!

I have an HP laptop that when googled says it shipped with a 120w charger, during a move that charger been lost but I have a 65w Dell charger which fits and appears to power everything on..
The HDD spins up and the CD drive laser makes the usual noises, fans spin, keyboard lights etc but the display does not come on. Not even a flash of bios screen or anything. The same result when I remove the HDD. Is this a product of using the lower wattage charger? Or should I not waste my money buying a new one? Thank you!!

ChuckMountain

It depends, using a lower spec charger usually gives an error message in Windows anyway.

Depending on how much juice the laptop actually needs then it is likely the battery will not charge whilst the machine is running.

However for quite a while, not sure if it is still the case dell and hp laptop chargers looked the same but weren't compatible.

EndlessWaves

Lower wattage just means it'll charge the battery more slowly and won't affect the laptop turning on (provided the battery is present and partially charged).

It's voltage that is crucial, just because it fits doesn't mean it's the same voltage and if you connect a different voltage of charger then it could damage the laptop.

techquest

Agree with @EndlessWaves.

The voltage should be on the laptop base. You could be causing damage if it does not tie in with the correct charger.

techquest

What model is the Laptop?

spideypunk

Thanks for the reply, much appreciated.

It is a HP Pavilion DV7. Putting it into YouTube the plot thickens, it’s possible the GPU has overheated causing black screen of death!

John7

You cannot make a diagnosis like that until you use a power adapter that has the same voltage and power (Watts) output (IMHO). The one you are using has half the power of the original and will not supply enough current to drive CPU/GPU, unless you are confident that the laptop battery has good charge and can supply the requisite power.

techquest

Your PSU is 18.5V 3.5A 65W

https://www.amazon.co.uk/Laptop-Charger-Adapter-Pavilion-EliteBook/dp/B07FZYXX8K/ref=sr_1_1_sspa?hvadid=79920783497215&hvbmt=bb&hvdev=c&hvqmt=b&keywords=hp pavilion dv7 charger&qid=1562683838&s=gateway&sr=8-1-spons&psc=1

The Dell PSU could well be 19.5 v which I know they used to produce with a similar plug to that of the HP PSU's plug.

So sadly you might well have blown the MB or CPU etc, hard to tell. You could check to see if there is any output to a monitor or tv by connecting either the VGA or HDMI outputs to a TV/Monitor. That way you could see if any signal at all is coming out of the laptop. But you would need the correct PSU to do so or you risk more damage using the wrong psu.

As @John7 states you would probably not have the correct voltage to make it work.

The correct 18.5V 3.5A 65W will be written on the base.

The output of the Dell PSU will be written on the back of the PSU. What do the numbers say. Might need a magnifying glass to read.

John7

It's highly unlikely that a PSU voltage which is one volt lower than design voltage would "blow" anything.

It is very likely that using a PSU with half the current capability will be unlikely to provide sufficient power to drive hungry components such as CPU/GPU (if the on-board battery is depleted)!

ChuckMountain

Agree with John7, 1 volt would be well within tolerances for a power supply adaptor and/or laptop to handle.

As stated before there was a compatibility issue based on the signal from the psu that meant an hp and dell were incompatible even if the same voltage and power output.