1 Slow Performance without proper Power Adapter after update on M4800?
Intermittently, since I purchased my laptop 3.5 years ago, I have noticed a problem where I plug in my official Dell 180W power supply into my Dell Precision M4800 laptop, and the Dell software would inform me that the power supply wasn't recognized and that it was under 150W. But, this usually resolved itself after a few minutes, or else I could unplug and re-plug the power supply and everything would be fine.
The bad news when this bogus error happened was that my CPU clock was slowed from 3.5 GHz to 0.35 GHz (a factor of 10!), which essentially made the PC nearly unusable.
A couple of weeks ago, my laptop underwent a software update, and now 9 times out of 10, the official Dell 180W power supply which was shipped with my laptop directly from Dell is incorrectly recognized as being unknown and under 150W.
This is clearly a software error on Dell's part, because it started occurring immediately after the software update and doesn't resolve by itself any longer, and also does not resolve by unplugging and re-plugging the power supply.
I would really appreciate it if someone at Dell would read this post and actually look into getting this problem fixed. I am not the only person who has experienced this problem, as there are at least 2 other posts (and multiple responses) from as far back as 2014 with a similar issue. As a pointer of where to look: in the communication between the laptop power drivers and the power supply, either the drivers or the power supply is causing the problem. It shouldn't be too hard to modify the driver software to properly handle the situation and avoid this debilitating roll back of the CPU clock speed.
As one other poster pointed out: the M4800 is only drawing 35W, why, then, do you need a 150W minimum power supply attached to the bloody machine?? Maybe the battery can't be quickly charged with a 50W power supply, but surely the clock speed doesn't need to be cut by a factor of 10 in even that extreme power situation.
Sheesh, guys, it's a Dell laptop, a Dell power supply, and Dell software: it certainly seems like there can't be any finger pointing at some mysterious 3rd party misbehaving and magically causing this problem with Dell having zero ability to do anything about it. Seriously, can't you get this right?
Is this a good question?
Hi @justinrunyon ,
When you said it was updated only a few weeks ago, was this a Windows update?
Have you checked that Windows didn't replace the appropriate drivers with its' generic own for your model?
Looking at the support page, there have been a lot of updated drivers (Power manager for one) released by Dell in 2018.
Just a thought.
by jayeff
Hi @justinrunyon
Well, I would suggest you getting another known working adapter to check if it works.
I know sometimes bad dc adapters, worn out cables / DC Jack, Dallas chip? can cause this weird issues. that is why it could be possible that it is trotting your pc processor frequency..
by Augustine
many of Dell's laptop power supplies have a chip inside that communicates with laptop "through center conductor" when this chip cannot with the laptop, it defaults to low power. That forces the dell laptop owner to buy prpietory dell power supplies. Good news 150w dell PS new for your older Dell is dirt cheap. oh buy the way in low power mode the laptop battery won't charge. even after 10 days. If you put a new battery in without the old PS it will jump to full processor speed until the constant current protection low voltage circuit warning trips. How ever if you put in a charged battery new or old without turning on the laptop it can sometimes initialize the power supply identity protocol . Then try replugging in a known Good Dell PS rated for your laptop . But don't take my word for it. It is so well documented, blogs spend a great deal of text on it. 1 last note the ID chip in PS can fail simultaneous during a bios update or a operating system without causality, I have also heard PS id failure due to wrapping the cable around older power block after 2 years of use. Gooder news your laptop is still OK as long as the power port is still rigid.
by Davidmsh