I previously owned a Dell XPS 13 9343 and it was a great device! I expected a solid upgrade going to the 7390 2-in-1. But I can't say I'm pleased. I got the really expensive model, 1TB drive, 32GB memory, QHD display.
Yes, I know the QHD display draws more power than the FHD. Sadly, the FHD display isn't even available with the large SSD and memory... Anyway:
== Regarding the battery ==
As other have noticed, the battery life is pretty abysmal. I get up to 5 hours at low screen brightness and just browsing the web. I have no idea what was different about the devices tested by Anandtech, cnet, laptopmag and others, but they all easily got 8 hours out of the QHD, up to almost 14 hours for the FHD model. But what Dell is shipping to people seems like a different deal. And I've read people calling Dell and getting told that it's normal for the battery to run out after 3-4 hours. Very disappointing for a device clearly aimed at mobility.
== Regarding thermal management ==
My old Dell XPS 13 ran cool and quiet. The fan NEVER turned on during normal use unless I was maxing out the CPU. In this new model, the fan is CONSTANTLY running on low. The CPU temp, just writing this forum post, hovers around 44° C in a 23° C room. Maybe the thermal compound and/or its application are rubbish? But this can't be intentional. Especially after all the marketing regarding Intel Athena... I'd be totally fine with much more aggressive throttling and lower performance (as if you even need "performance" for most tasks) if that would shut up the fan and extend the battery life. I think there's something massively wrong with the engineering of the thermal management.
All in all, this is a pretty disappointing deal for 2500USD, especially compared to the old one. Honestly I'm not sure what to do. Maybe I'll upgrade the thermal compound on the CPU. Maybe I'll just have to return it... What a shame.
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