I have a 90W USB-C power adapter that goes 20V/4.5A and I use a USB-IF certified USB-C gen 2 (10gbs/5A/100W), and when I connect it through the thunderbolt port on my Dell XPS 15 7590, a warning that tells that the charger is slow appears. Also, on the BIOS, it only recognize my charger as a 65W charger. I have also tried a Macbook pro 87W usb-c charger and the same message appears. The power adapters and usb-c cables are not the problem since I have tested many.
How can I resolve this? The max input could not be 65W since Dell sells a 130W usb-c power adapter for this laptop...
Please help, I do not want to use an enormous 130W adapter when travelling, but 65W is way too slow.
USB-C devices are not required to take any power level offered by the charger. For some reason, XPS 15 tends to accept 65W or 60W @ 20V, even if the charger offers some more. Mind anything under 130W tends to result in a restricted mode, and 130W is in fact above the USB PD standard (max 100W), so I wouldn't expect anything non-Dell to work. Though, 60W is more than enough for office work and web browsing, as a travel charger...
@alex345 you can't resolve this, because it's a firmware limitation imposed by Dell itself. Dell systems at this time seem to be limited to drawing 65W from any non-Dell charger, even when the charger offers more and the system could use more. I wrote an entire thread about this here. I personally travel with a 60W charger but I've resigned myself to the fact that it's only useful for charging my system overnight and keeping its battery level maintained. I basically don't count on being able to use it to charge my system and run it at the same time, only one or the other.
@samos1111 no 65W is not enough for a system that requires 130W. On both the XPS 15 and similar Lenovo ThinkPad X1 Extreme models, using a 60-65W power source results in noticeable performance throttling even without the GPU active (and very noticeable throttling with it active) and incredibly slow battery charge time. I manage to make it work for what I need to do on the road, but I can absolutely see why it might not be viable for others.
Of course it is throttled down a lot. The GPU seems to be throttled more than on battery and I couldn't change this. The CPU uses the "on battery" values of the power profile and can be un-throttled in the advanced settings. Whether 60W is enough depends a lot on what you're doing. When idling, the consumption can be less than 10W. With full CPU load it reaches 90W, so may need to drain the battery in addition.
I was using a 45W round-plug charger for travelling light with the 9550 and it used to work fine for me (no serious work though). But recently I was having issues because it periodically throttles down really heavily (also on battery).
Wow, Dell has no real reason to limit this to 65W, as Apple, Lenovo, Microsoft and many others can all be charged from usb-c at more than 65W. What a bad move. Please Dell make a firmware update.
@Lobotomik Since I wrote my reply above, users have confirmed that the new XPS 15 9500 supports at least up to 90W charging from third party sources — unclear about 100W last time I checked — but I haven’t seen anything about this limitation being retroactively removed from earlier models. But I agree this should absolutely be fixed and seems a completely arbitrary and unnecessary limitation.
Ooops! I misread I misread the title for this discussion. For what it's worth, my computer is not an XPS 7590, but an XPS 9750. Not that I think it makes much of a difference for this matter...
Is there any way to ask Dell to support this fix? It is a two-year old computer, but it cost me quite a fortune in its day... And I'm sure that it would only take changing a couple of values in some table and distribuite with their next BIOS update. It can already take 130W from a Dell dock which is outside USB PD bounds, so the hardware is certainly up to it.