Precision 7530 & Precision 7730 owner's thread

It's more true for lithium batteries than it has been for cadmium, alkaline, etc.

Well, that is what happens, but the battery (even if it's not discharging) is left at full capacity, and the voltage difference causes a lot of permanent electromigration that degrades the capacity of the batteries. It's always been a rule that for long-term storage, it's best to discharge/charge a lithium battery to ~50% and leave it there, or in the case of a permanently-plugged in notebook, use charge limiting so that it doesn't go all the way to 100%.

 

Is the storage effect accumulative, or will frequent undocking alleviate that? For example, I typically work on my porch on battery for about an hour a day, so the battery probably discharges to about 50% during that period. I did find some info that said 20% loss of capacity for a year of storage at 100% at room temperature is probably typically. But I think that was for permanent storage.

TBH, it sounds like you have had worse luck with your battery than I did, despite only charging to 80%.

I did order a new battery, so I'll probably try that anyway. I'm not really finding much for recommendations on Dell's site. I assume this is what the BIOS option for "Primary AC Use" means. Does anyone know the exact charge limits it imposes? One would think that might be the default, given the nature of the laptop.

(I just enabled it, but it still is reporting the capacities (8509 mAh for full design capacity, 4920mAh for last full charge)

 

Mine is also set up as "Primary AC Use" and my assumption is the same. I don't know of any charging limit with this setting, though.
Linux reports about 70% battery capacity, but Dell BIOS reports a battery health higher than 90%... (my laptop is nearly 3 years old)
There's been huge improvements in battery life, i guess thanks to BIOS updates (and maybe Linux power management).
But today I realised CPU frequencies won't go higher than 2.4 GHz when running on battery. Setting higher limits or performance CPU governors in tlp doesn't help. I guess newer BIOS heavily throttle CPU max frequencies on battery. Any ideas to unlock that?

 

I actually only started using the charge limiter functionality with the latest battery I changed to, early in 2020.

I have had my notebook almost permanently plugged in since April 2020 when the Apocalypse arrived, and the battery wear is still sitting at 4%, and I can get ~8 hours out of the battery when unplugged (though not in Linux, and this might be due to the 7530/7730's poor management of GPU power, which has been fixed in subsequent generations).

Don't use 'Primary AC'; instead, configure custom limits at 50 and 80% minimum and maximum respectively. Primary AC doesn't do anything, as far as the battery charging limiter is concerned.

 

Battery Management System is pretty sophisticated. I leave this to BMS, and mine is plugged all the time. BIOS is on AC.

There are too many contradicting views on the Li battery management, and most of them are done with an authorative voice. Do you own homework, or stop worrying altogether - has been my approach. if I need to buy a new battery - so be it. Just don't buy cheap fakes.

 

Anyone else have issues with the fan running on max all the time from the moment you press the power button? I've set the power management cooling to "passive" and set the "quiet" fan mode in the power manager but nothing has changed. Everything is also fully updated to the latest bios and thermal frame work.

 

Check Windows advanced power options, look for PCIe "link state power management", and make sure that it is set to "maximum power savings".

 

Yep that is also set as such as well. Perhaps I have a dud and don't think I should have to undervolt or install fan control to get around this. I've owned several precisions which were all very quiet. I'll see if I can get prosupport to fix it.

 

Can you check your CPU temperature while the system is idle? Mine sits in the upper 40's / low 50's when idle, and maybe upper 50's / low 60's if I am doing light browsing or something. If that's the case and the fans are still roaring, something definitely seems off.

 

I think I might have found out why - this gray fan cable has been disconnected: