Precision 3660 Bank Screen after Bios Update from DCU

he system was fully functional before installing the official Dell BIOS 2.32
(released December 2025).
Immediately after the update, the workstation enters a permanent boot loop,
powers on automatically when AC is connected, shows no video output,
and all BIOS recovery procedures fail.

This appears to be a defective firmware issue rather than a hardware failure.

More Over this case has been replicated to one of my MOC device

Additional details:

The system was fully functional before installing the official Dell BIOS 2.32
(released December 2025).

Immediately after the update, the Precision 3660 entered a permanent boot loop:
- powers on automatically when AC is connected
- no video output (black screen)
- fans stop and restart continuously
- BIOS recovery procedures (Ctrl + Esc, USB recovery) are not working
- this model has no CMOS clear jumper

The workstation is now completely unusable.
This strongly indicates a defective Dell firmware rather than a hardware failure.

I would like this issue to be escalated as a firmware quality incident.

We have notified the platform team of your thread concerning the Precision 3660 issue.

BIOS 2.32 has been removed from the Precision 3660 Drivers & Downloads.

* Disconnect the power cable from the rear of the Precision 3660
* Press and hold in the Precision 3660 power button for 8 seconds
* Reconnect the power cable to the rear of the Precision 3660
* Turn the Precision 3660 on. What happens?

It fail to boots not thing happen. Only darkness =]

Before sharing my hypothesis, I would like to describe the observed facts.

Observed behavior on the affected Precision 3660:

- No video signal output to the monitor.
- Pressing Num Lock or Caps Lock does not trigger any indicator LED response.
- The CPU fan and exhaust fan do not spin.
- The CPU heatsink does not become warm, indicating the CPU does not appear to be running.
- The power button LED is solid white.
- The rear power LED repeatedly turns on for approximately 1 minute, then turns off for about 5 seconds, in a continuous loop.

Confirmed update results:

- Dell Command Update (DCU) version 5.4:
  The BIOS update completed successfully on my Precision 3660.

- Dell Command Update (DCU) version 5.5:
  On another Precision 3660, the system became non-functional after the BIOS update.
  The motherboard was replaced under warranty.
  However, after applying the BIOS update again using the same DCU version (5.5), the issue reoccurred and the system became non-functional once more.

After the failure occurred twice using DCU version 5.5, I realized that the DCU version itself might be a factor that determines whether the issue occurs or not.

Based on these observations, I suspect that the DCU version used during the BIOS update may be a key factor.

The BIOS version applied during the update was 2.32.0.

As of 2025-12-16 05:00 (GMT), the latest BIOS version available on the Dell driver download website is listed as 2.31.0.
However, at least via Dell Command Update, BIOS version 2.32.0 was still being offered as of 2025-12-16 02:00 (GMT).

After applying BIOS version 2.32.0 through Dell Command Update, the motherboard on this system failed for the second time.

The same here. Removing all devices, (mouse, keyboard, SSDs, even RAM(!)) doesn't help. The screen is always blank. No keyboard input is accepted (F2,F8,F12, Ctrl+ESC, Ctrl+DEL for 30 Seconds). No LED on the keyboard lights up. Removing the CMOS battery for 1-2 hours doesn't help. Do I need to buy a new motherboard?

I have exactly the same issue. Periodically, I would run DCU & install updates. PC was running fine, until an unprompted DCU pop-up appeared on 12/12, saying that 2 updates were recommended. I closed open programs, then sat at the PC & watched the firmware being unpacked & installed. This wasn’t just a BIOS update (for me, having not used the PC for 2 days) it was a package updating motherboard firmware, too.

After appearing to be successful, an automated re-boot lead to exactly the same issue as you have been having. I haven’t been able to use the PC for 5 days, now. Extremely inconvenient, for a multitude of reasons.

I searched for solutions online, did the hard reset, removed the CMOS battery, downloaded the new BIOS, renamed & copied to a USB drive, all with no fix.

I used online chat, to convey my disappointment of the fact that the “updates” bricked a perfectly operational system. After being offered a number of solutions (less than I’d already tried, numerous times), there was no resistance. A technician was scheduled.

Fortunately, mine is still covered by “basic” support. The technician is arriving today, with a new motherboard & thermal paste.

Part number for the mobo is PRR48.

Same here. Three PCs are dead after updating the firmware to 2.32.0. via Dell Commandline Update. Affected mainboard models seem to be DELL OPRR48 and DELL 0KM9JV. 

Its like we are several sharing the same issue! I confirm in my case Dcu 5.4 was used

@DELL-ChrisM2​ Of course I tried this several times, no changes at all, BLANK Screen

I can see Dell has removed 2.32 Firmware update from Official site for Precision 3660 Drivers Support page

I have 4 Desktops PCS Dead in my company all out of garantee and support since 2 months. Will Dell provide any solution in that case please?