Power cable question

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pampoenskyf

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So the power cable for my laptop is faulty and I must get a new one. There's a universal charger at Chaos computers I'd like to get. On the phone the salesman asked me if I need the 65W or 90W charger :wtf:

Now I know a dick from a vagina but this is Greek to me - missed the elec 101 crash course class. On the bottom of the laptop it reads "Input 18.5V & 3.5A". How does this effect the wattage? I don't wanna get the 90W if it will turn the laptop into a suicide bomber :erm:
 
Rather look under the old charger for it's specifications or google your laptop for more information on the charger requirement. You can't go wrong by taking a 90 W charger as long as the voltage is correct. You don't know how much spare capacity should be built in if you use aforementioned formula to calculate the needed wattage to charge the battery.
 
I'd just buy the 90W charger, unless there's a major difference in price. The worst that could happen is that your laptop recharges a bit faster.
 
I've heard that if the Wattage is too big the laptop could blow. Not sure what 90Wwill do in this case..if anything
 
Stokstert said:
Rather look under the old charger for it's specifications or google your laptop for more information on the charger requirement. You can't go wrong by taking a 90 W charger as long as the voltage is correct. You don't know how much spare capacity should be built in if you use aforementioned formula to calculate the needed wattage to charge the battery.
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Thanks. Checked. Definitely a 65W
 
It shoud be fine as long as the voltage is the same and the wattage greater than or equal to the one you're replacing. 90W doesn't mean that it will supply 90W, it means that 90W will be avilailable if required. The laptop will draw what it needs. If the wattage is lower than the one you're replacing, then it's a problem.
 
If a too high wattage would blow the laptop, then my PC would've blown up because it only uses 500W from the 850W PSU ;)
So it is like how Abzo said it: your laptop will consume only as much power as it needs from the PSU.

If the PSU's wattage is too low, then the laptop would try to draw more current than what the PSU's components are rated for and then it would overheat and break/blow.
Also don't buy TOO big PSU's (like 3x more than what you require), because then the PSU isn't as efficient any more. They're typically the most efficient between 45-75% load.

It is the too high voltage (and temperature) that is harmful to computer components.
 
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abzo said:
It shoud be fine as long as the voltage is the same and the wattage greater than or equal to the one you're replacing. 90W doesn't mean that it will supply 90W, it means that 90W will be avilailable if required. The laptop will draw what it needs. If the wattage is lower than the one you're replacing, then it's a problem.
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Pada said:
If a too high wattage would blow the laptop, then my PC would've blown up because it only uses 500W from the 850W PSU ;)
So it is like how Abzo said it: your laptop will consume only as much power as it needs from the PSU.

If the PSU's wattage is too low, then the laptop would try to draw more current than what the PSU's components are rated for and then it would overheat and break/blow.
Also don't buy TOO big PSU's (like 3x more than what you require), because then the PSU isn't as efficient any more. They're typically the most efficient between 45-75% load.

It is the too high voltage (and temperature) that is harmful to computer components.
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Ok, so given the specs of 18.5V & 3.5A would you buy the 65W or 90W charger? :D
 
pampoenskyf said:
In that case the rule of thumb would be to adhere to the formula of P=IV provided that the voltage rating corresponds with that of the laptop spec?
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It's just that the 64.75W is too close to the maximum 65W so I'm not comfortable with that. Power supplies are usually designed to supply more than the load requires anyway. Personal preference.
 
Parsonally I would go 65W. Too strong PS will give move voltage under maximum laptop load and bigger overshots if load is interrupted. If 65W is enough, stay with 65W
Matter of power is not so important if 50% over. But check if thickness of the internal pin matches the new plug. If new plug has bigger internal diameter, it would give poor contact. I saw many cases external cylinder is matching, but internal doesn't.
 
pampoenskyf said:
Not a single 65W charger in any of western Cape branches
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Chaos will no longer stock this brand" XGR Universal notebook charger". They've had too many comebacks. Instead they've replaced my broken one it with the more consistent Huntkey universal adapter. Very good track record on these
 
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