This is my bios version: DMI: Dell Inc. Precision 7530/0425K7, BIOS 1.12.1 11/11/2019

Hi, I have Precision 7530 and I have the exact same problem

I hadn't tried dell support yet.

I found out that the problem disappears if I downgrade BIOS to version 1.7.0

@pgregy,

We appreciate your efforts in running the trouble shooting steps. 

Dell has tested Ubuntu 16:04 and Ubuntu 18:04 operating system on your system model so we recommend installing these to versions. As per the order details system is shipped with Ubuntu 16:04.

Were you having the same issue when you were using Ubuntu 16:04 that was factory shipped? ^KR

Hi pgregy,

 I appreciate your response, and it's nice to hear that you were able to fix the issue by downgrading the BIOS. Updating the BIOS was the first thing I did when I received my 7540 and it looks like I can go back as well (from v1.6.0 to v1.5.1 in my case). Unfortunately, I won't be able to test this until Monday, as I left the laptop at my office over the weekend.

 I hope this fixes the issue for me as well, but either way, thank you for reaching out. Your help is very much appreciated. Also I hope you have a Happy New Year.

Thanks,

Dale

I downgraded the BIOS from v1.6.0 to v1.5.1 and I still see the same problem. That's a shame because aside from this issue, I really like this laptop. Not being able to boot from battery is a deal breaker though.

I was able to downgrade the BIOS below v1.5.1 by disabling BIOS security mitigations (SMM). I took the laptop all the way down to BIOS v1.0.0. And it works now. The laptop boots from the battery just like its supposed to. I'll try upgrading one version at a time until I can determine which BIOS version breaks my ability to boot from the battery.

So I can confirm that for my Precision 7540, BIOS versions 1.0.0, 1.1.3, 1.2.3, and 1.3.3 all work as expected, with respect to my specific startup issue. With BIOS versions 1.5.1 or 1.6.0, the laptop won't boot Linux unless the AC adapter is plugged in. This issue doesn't seem to affect Windows, but it seems to affect multiple versions of Linux including Ubuntu 18.04 which is supposed to be officially supported on this hardware. Does anyone from Dell have any ideas why this may be the case?

Thanks,

Dale

Hi,

I came to this thread looking for the solution to a similar problem that I am currently facing with my Dell Precision 7530 with Ubuntu 18.04. It does not boot unless the laptop is connected to AC power. This was not always the case. A few days back, I accepted the system updates and got them installed (I did not check what these updates were). The problem has started since then.

Could you please have a look into it?

Thanks

[In case you need to know about the default OS that was shipped with the laptop, it was an invalid/inactivated Windows OS.  I specifically requested for Ubuntu 18.04, but the vendor had only 16.04. So we had agreed that I would install Ubuntu 18.04 on the laptop after I received it.]

I suppose I have the same problem.

• Windows boots up normally, Ubuntu does not.
• I am not exactly sure when the problem first arose but it was sometime in late december. I did a Dell-update in Windows (I use both OS daily) back then.
• I use a Latitude 7300

Hope this helps the support-team fixing the problem. Thanks

It's interesting that this issue is affecting different models. I'm still inside the return window for my laptop, but if it's clearly a BIOS issue, that at least makes me more confident in the actual hardware. And it's more likely that Dell will fix the issue.

Please try booting with the kernel param "dis_ucode_ldr". I believe there was a CPU microcode update in the newer bios which is causing issues with the newer kernels. The stock 18.04LTS image actually ships with a customized 4.15 kernel, which doesn't have this issue with the newer bios versions.

I've just installed the stock LTS version and the problem still exists.

I have this same problem on the same laptop.