Can a 65W adapter slowing my 95W dell laptop?

Question

My highly configured Dell Latitude E6410 laptop has become extremely slow, even for browsing or multitasking for the past 14 months. I thought it was because of Windows, so I tried fresh installations of win7, 8.1 and 10 - Still didn't solve the issue. But it was amazingly fast when it was new. The laptop originally came with a 95w power adapter, which I lost, and using a 65w adapter. Could this be causing the trouble? Machine also seems to overheat quickly.

Full specs

Core i5 2.5 ghz

8gb 1600 mhz

Nvidia M3100 graphics chipset

SSD 256GB

Answer 1

As Sean already wrote: A low power adaptor would make it charge slower, but it will not actually slow down the laptop.

... except in some cases where the laptop is made by Dell.

Dell uses locked powersupplies. It recognises the PSU as Dell branded. If it does not detect that (e.g. if you replaced a 95W Dell PSU with a 65W generic one) it will complain at boot and run the laptop is low performance mode. The linked article is for alienware laptops (bought by Dell) but I have seen the same on the Dell lattitude series.

Answer 2

You can use a compatible higher or lower wattage adapter without issue, but it won't make your computer charge slower/faster or operate differently. Your power adaptor should provide a steady voltage over a range of current.^source

It may only slow your laptop when your voltage is too low or to high, which can lead to odd and unexpected behaviour and it may damage your equipment, but not the current.

However when energy consumption is too high (it doesn't charge quick enough and it drawing energy too much), it may heat up or melt power supply or cord and shorter lifespan of your power adaptor and may lead to operating system stability problems or crashes. See: Laptop power supplies, does current matter?

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Troubleshooting on Windows

Potential reason that your laptop may slowing down while charging is because of switching into different computer's power settings, so your laptop could behave differently and overheating, or some applications are activated only when you're charging (anti-viruses, disk compression tools, etc). To check or adjusting these settings of your Power plans, go to Control Panel (list all the items), and select Power Option. You may create your own Power Plan (Create a Power Plan). See: FAQ - Power plans

You can also investigate the issue by running Power Troubleshooter (Power in Control Panel). See: Laptop overheats when plugged.

Answer 3

a low power adaptor would make it charge slow but it will not actually slow down the laptop

https://www.quora.com/What-is-the-consequence-of-using-a-lower-wattage-power-adapter-with-a-laptop

Answer 4

Are you sure the battery is alright ?
Batteries are consumables. They do wear, even when not used.
A worn battery (and after 14 months it could be worn...) is continuously being recharged. This can cause the laptop getting very hot which in turn causes the CPU to "throttle down" to prevent overheating.

The under powered power-supply might also be part of the problem. The original PSU had enough juice to power the laptop at full-speed and recharge the battery at the same time, but the current one not so much. As a result something has to give: Charge the battery slower or throttle down the laptop, possibly both.

Try to operate the laptop WITHOUT battery. (Most laptops allow this.) See if the laptop runs faster/less hot.
Also run it on JUST the battery and see if you get reasonable lifetime out of the battery.
That should tell you if the battery is end-of-life and needs replacing.

That is assuming the new PSU is suitable. If that is out of spec it can cause all sorts of weirdness.
So double-check if the replacement PSU you are using now is really suitable. It should have the same output voltage (within 10% of the original PSU, if it is not exactly the same a little higher is better then a little lower). And ideally the replacement should be able to deliver at least 2/3 of the original power (you're borderline OK there) but more is always better.