Safe to use lower watt PSU? (laptop)

[moonedyou]

I'm currently using a 90w power adapter on my Acer predator G3-571 laptop that requires a 180W power adapter (voltages match though). It works fine when just surfing the web and stuff , but when I jump into a game it switches back and forth from Battery power to PSU power and the GPU downclocks severely and lags and the backlit keyboard flickers. Is there any risk of damaging the laptop or any of the internal components? Also when i'm just running on the battery While gaming the GPU downclocks, but I assume this is because the battery alone cant provide enough power? 

[BigDamn]

The battery can only discharge at a certain rate, so it won't be able to power the CPU and GPU at full load. When power enters the laptop from your external PSU it directs some of that power to the battery for charging purposes and a majority goes directly to the components. Using a lower wattage PSU for a laptop is no different than doing the same on a desktop. You are going to fry the PSU and most likely the components in your laptop, including the battery. Why in gods name would you use a 90w power adapter on a laptop that requires double that. Desperation is one thing but jesus christ man. At best you will be able to charge the laptop while it is completely off. You should certainly find a better power adapter.

[it_dont_work]

9 minutes ago, moonedyou said:

 Is there any risk of damaging the laptop or any of the internal components?

Also when i'm just running on the battery While gaming the GPU downclocks, but I assume this is because the battery alone cant provide enough power? 

-Pretty much, as long as it's not a cheap adapter and its providing smooth reliable power you can't damage anything.

-Downclocks because of energy constraints, this can usually be changed in power management settings, expect less running time if you change them.

-The power adapter is sized to allow high system load and charge the battery, smaller adapter just means less power in than being used and your battery will drain slowly, and only charge effectivly when being lightly used or off. 

[badreg]

5 minutes ago, BigDamn said:

You are going to fry the PSU and most likely the components in your laptop, including the battery.

Wait, what now? The power adapter will only provide the amperage it is rated for, no matter how much the device is asking for. This is like saying charging a phone with a 1A charger will fry the charger and the battery if the phone is capable of charging at 2A.

[BigDamn]

7 minutes ago, badreg said:

Wait, what now? The power adapter will only provide the amperage it is rated for, no matter how much the device is asking for. This is like saying charging a phone with a 1A charger will fry the charger and the battery if the phone is capable of charging at 2A.

You would be right if his laptop wasn't experiencing the issues that he described. Backlit keyboard flickering? It's drawing as much juice from that PSU as it can and it will run HOT. Just because its rated to run at 90w doesn't mean it should. My laptop charger is 180w and at full load (CPU and GPU) while plugged in it uses around 130-140. He is damaging his laptop and the PSU is going down with the ship. Charging a phone is not comparable here.

[moonedyou]

15 hours ago, BigDamn said:

The battery can only discharge at a certain rate, so it won't be able to power the CPU and GPU at full load. When power enters the laptop from your external PSU it directs some of that power to the battery for charging purposes and a majority goes directly to the components. Using a lower wattage PSU for a laptop is no different than doing the same on a desktop. You are going to fry the PSU and most likely the components in your laptop, including the battery. Why in gods name would you use a 90w power adapter on a laptop that requires double that. Desperation is one thing but jesus christ man. At best you will be able to charge the laptop while it is completely off. You should certainly find a better power adapter.

unfortunately it came with the laptop when I bought it used, but i'm going to buy the correct one asap. So my laptop is going to blow up from what you're saying? lol 

 

that's to bad I was really hoping this laptop wouldn't be damaged, I guess i'll just get rid of it

[aezakmi]

• Let's say you drive a bus that is 9 meters long and want to park it in your garage, that is only 4m long, will it fit?
• You bought a brand new Apple Car but it came without the steering wheel (costs $5000) however you have a Civic steering wheel in your garage, would you be able to use it in your new car?
• Your uncle... Bob, wants you to go to the supermarket and buy him two beers, each one costs $5 but he only gives you $6 and a bent quarter that is most likely to be rejected by the cashier, is it enough?

 

_Answers:

Spoiler

^{a) no}

^{b) no}

^{c) no}

 

Ergo you can't use a 90W power supply to power something that needs 180W

 

 

 

[BigDamn]

Just now, moonedyou said:

 

unfortunately it came with the laptop when I bought it used, but i'm going to buy the correct one asap. So my laptop is going to blow up from what you're saying? lol 

lol no it won't blow up, but you are certainly doing damage. Keep the laptop shutdown and charge it too 100% and you'll be fine.

[moonedyou]

14 hours ago, BigDamn said:

lol no it won't blow up, but you are certainly doing damage. Keep the laptop shutdown and charge it too 100% and you'll be fine.

So you're positive it's damaged? like all the components? 

 

15 hours ago, it_dont_work said:

-Pretty much, as long as it's not a cheap adapter and its providing smooth reliable power you can't damage anything.

Nothing to worry about?

[BigDamn]

56 minutes ago, moonedyou said:

So you're positive it's damaged? like all the components? 

Not saying the laptop is currently damaged, I'm saying it can be damaged. Best bet is to get a new 180w adapter asap.

[Guest]

1 hour ago, badreg said:

Wait, what now? The power adapter will only provide the amperage it is rated for, no matter how much the device is asking for. This is like saying charging a phone with a 1A charger will fry the charger and the battery if the phone is capable of charging at 2A.

Well.. we don't what kind of adapter this is.  Just like a desktop PSU, a laptop PSU can put out over it's rating as long as that's what's demanded of it.  We don't know if the PSU has OPP or OCP.  

 

If it doesn't, worst that can happen is the power brick blows up.

 

[moonedyou]

18 minutes ago, jonnyGURU said:

Well.. we don't what kind of adapter this is.  Just like a desktop PSU, a laptop PSU can put out over it's rating as long as that's what's demanded of it.  We don't know if the PSU has OPP or OCP.  

 

If it doesn't, worst that can happen is the power brick blows up.

the adapter model number is XCP2-1001

[badreg]

23 minutes ago, jonnyGURU said:

Well.. we don't what kind of adapter this is.  Just like a desktop PSU, a laptop PSU can put out over it's rating as long as that's what's demanded of it.  We don't know if the PSU has OPP or OCP.  

 

If it doesn't, worst that can happen is the power brick blows up.

 

Assuming that the adapter has no OCP and blows up, what happens when it fails? Does the adapter send a surge to the board and kill it? Isn't there some kind of OCP on the input circuit itself, or does this not matter when the adapter blows up?

[moonedyou]

41 minutes ago, jonnyGURU said:

Well.. we don't what kind of adapter this is.  Just like a desktop PSU, a laptop PSU can put out over it's rating as long as that's what's demanded of it.  We don't know if the PSU has OPP or OCP.  

 

If it doesn't, worst that can happen is the power brick blows up.

so there's nothing really to worry about my laptop being damaged? only the psu can be damaged?

[Guest]

13 hours ago, moonedyou said:

so there's nothing really to worry about my laptop being damaged? only the psu can be damaged?

It's switching to battery just like it would if you unplugged the brick.  The GPU downclocks, which its supposed to do if there's not enough power, which is pretty typical for gaming laptops running on battery power.  Seems fine to me.  Just the brick will likely die sooner than later.

 

13 hours ago, badreg said:

Assuming that the adapter has no OCP and blows up, what happens when it fails? Does the adapter send a surge to the board and kill it? Isn't there some kind of OCP on the input circuit itself, or does this not matter when the adapter blows up?

The laptop isn't going to have OCP for an underpowered brick.  The laptop doesn't "know" what power brick is plugged into it.  It doesn't know that it's only a 90W and not  a 120W.

 

The good thing is, the power from the brick essentially goes "through" the battery.  It's not like a relay in a UPS switching back and forth.  It could be switching to battery for a number of reasons.  The voltage is dropping because the brick is overwhelmed, or the brick actually has OCP and is shutting down.  We don't know.  

 

I Googled the part number provided by the OP.  "Xtreme Cables" isn't exactly a brand name.  From the pictures I see, it seems pretty crappy.  No UL either.  Thing might catch fire for all we know.  I'd just as well replace it ASAP.

[moonedyou]

12 minutes ago, jonnyGURU said:

It's switching to battery just like it would if you unplugged the brick.  The GPU downclocks, which its supposed to do if there's not enough power, which is pretty typical for gaming laptops running on battery power.  Seems fine to me.  Just the brick will likely die sooner than later.

Thanks I guess it'll be ok for short term use, i'm planning to get an original charger in a weeks time.

 

the universal charger is 90w, 19v, 4.47amps. The original charger it came with was 180w, 19.5v, 9.23amps, just to clarify. 

[Stefan Payne]

57 minutes ago, moonedyou said:

Thanks I guess it'll be ok for short term use, i'm planning to get an original charger in a weeks time.

by that time it might already be too late and your Laptop be dead.

 

57 minutes ago, moonedyou said:

the universal charger is 90w, 19v, 4.47amps. The original charger it came with was 180w, 19.5v, 9.23amps, just to clarify. 

Yes, and?
That all doesn't matter. The Important part is the quality of the part and we don't know it.

So its safer to assume its a fire hazard and you just might be killing your Laptop.

But hey, getting a new Laptop because of a shitty charger makes more sense than to not use it for a week or so...

[moonedyou]

20 minutes ago, Stefan Payne said:

Yes, and?
That all doesn't matter. The Important part is the quality of the part and we don't know it.

So its safer to assume its a fire hazard and you just might be killing your Laptop.

But hey, getting a new Laptop because of a shitty charger makes more sense than to not use it for a week or so...

thanks

 

[moonedyou]

Do all modern laptops and adapters have over current protection? 

[APasz]

All modern PSU's that conform to industry standards have some form of, final line of defence or last ditch overcurrent protection.

However treat it as if it doesn't exist at all. It's assumed that there is proper protection on the electrical circuit.

[moonedyou]

7 hours ago, APasz said:

All modern PSU's that conform to industry standards have some form of, final line of defence or last ditch overcurrent protection.

However treat it as if it doesn't exist at all. It's assumed that there is proper protection on the electrical circuit.

Thanks, I was asking because i'm temporarily using a 90w 19volt charger for my laptop that had a original 180w 19volt charger, so just incase something happens its nice to know it has protection.

 

will my laptop be damaged or blow up? I'm using a universal charger that's 90w, 19v, 4.47amps. The original charger it came with was 180w, 19.5v, 9.23amps. I lost the original that's why im using this one at the moment. what should I expect? 

 

Acer predator helios 300 

[Murasaki]

Lower wattage, slightly higher voltage and twice less current.. Your battery will charge slower?

[Bananasplit_00]

its going to charge slowly and might not even charge when running a heavy task but it should be fine otherwise

[moonedyou]

7 minutes ago, Bananasplit_00 said:

its going to charge slowly and might not even charge when running a heavy task but it should be fine otherwise

thanks for the response. i'll only be using it for a week or so that's when my new charger gets here. hopefully nothing blows up in the meantime lol

[Bananasplit_00]

Just now, moonedyou said:

thanks for the response. i'll only be using it for a week or so that's when my new charger gets here. hopefully nothing blows up in the meantime lol

there wont be a problem with anything blowing up, voltage is similar enough, its just able to supply half the amprage of the real one so charging will be slower