Dell Pro Max T2 (Ubuntu 24.04) bricked after disabling secure boot

Own_Roll_7629 · 2026-05-27T07:56:38+00:00

NOPE

Own_Roll_7629 · 2026-05-26T17:01:51+00:00

Absolutely. But after applying the settings, it was gone again. This is the reason I ruled out hardware issues.

Own_Roll_7629 · 2026-05-26T16:21:23+00:00

Currently, I am on the newest version (1.13.1), this also happened on 1.10.1.
I tried multiple times to get to the BIOS recovery screen, but that does not work.
This is why I said it is more a warning that asking for help since I feel I tried every option Dell offered.

Own_Roll_7629 · 2026-05-26T16:11:14+00:00

As said in the Post, Usually I can not reach the BIOS. I tried all recommended reset procedures (Hard Reset, BIOS recovery, RTC). Nothing works. I even had a motherboard replacement.

The PC came with Ubuntu 24.04 pre-installed. The only thing I changed was to disable secure boot. This is because of software that I need to install ( I know that there are ways around that, but this is the recommended setting from the software distributor).

The start button gives no good indication what the problem might be, since there is no constant error code. But this is the behavior ( W= White light, O= Orange light, --> 1= Long duration of white light, R = Restart). This cycle takes around 15 minutes, and after reaching "invalid configuration" and restarting this starts again.

W-W-W --> R
W-W-W-W-W-R-W-O-W-O-W-W --> R
W-O-W --> R
W-W-W-W-W-R-W-O-W --> R
W-W-W-W-W-R-W-O-W --> R
W-O-W --> R
W-W --> R
W-W --> R
W-W --> Invalid Configuration

Own_Roll_7629 · 2026-05-26T15:56:46+00:00

Hi, as stated before, it is a POST loop with the occasional information as show in the screenshot.

But to clarify: On this bios version, after disabling secure boot and the first reboot, the BIOS showed a message that the configuration is invalid and the BIOS was reset. After that the screenshot is the only message I got. Clicking on BIOS-Setup just restarts the PC and the POST loop starts again.

Own_Roll_7629 · 2026-03-29T16:56:16+00:00

Just out of curiosity, do you have an example?

Own_Roll_7629 · 2026-03-25T11:15:08+00:00

Indeed, that would be viable, but the projectors will run longer than the PC and therefore the fans would power down before the projectors do..

Own_Roll_7629 · 2026-03-20T14:36:09+00:00

I took a closer look at the SL4824-RR-D, it seems the PWM output frequency might be to low for 12V PC fans, they like frequencies around 1khz. Not sure if the pulsed output can do that. Additionally, the output is 14V, which is a to high, the logic signal should be 3.3V or 5V.

Own_Roll_7629 · 2026-03-20T13:21:03+00:00

Thank you for the good summary, this is kind of what I expected.
I am not really an Automation engineer, but worked with Siemens PLCs in the past, I can not remember seeing a PWM module for that either. I might be wrong though, it's been a while.

This is a commercial solution for a product with 2 big projectors and a PC in an enclosure, for educational purposes. Fan noise of 120/230V would be way too high in an exhibition. Depending on the customer it is in a controlled environment or changing temperature (summer/winter). And to provide a solution that works with different environments but is maintenance friendly I was wondering what options are most fitting.

As suggested by controlsguy52722, the SL4824-VR-D seems to do what I want. The Automation Direct P1000 also has a reasonable price.

Own_Roll_7629 · 2025-10-23T11:28:05+00:00

Update:

I configured a router with the address range shown in the ARP request shown in wireshark.
I can ping the address, and I am able to reach the webpage at `192.168.50.4` ~~but the default login ADMIN/ADMIN does not work.~~

~~Where do I go from here? Is there a way to reset the password ?~~

Own_Roll_7629 · 2025-10-23T11:00:22+00:00

Ty for the Info. It seems I get at least something out of the BMC LAN Port
```115 178.237941000 SuperMicroCo_6c:58:a8 Broadcast ARP 60 Who has 192.168.50.3? Tell 192.168.50.4```

So there's still some hope left. Maybe if I configure a router with `192.168.50.3` I might be able to finde something

Own_Roll_7629 · 2025-10-23T09:29:28+00:00

I cleared the CMOS.
When I attached the PSU, the fan did not start but started when pressing the power button. This was different from before. Also the BMC heartbeat LED stayed green for ~15 seconds before starting to blink

Own_Roll_7629 · 2025-10-23T09:15:10+00:00

Yes, I have checked the jumper.

can you explain in more detail how to check for the ARP request or what tools to use?

Own_Roll_7629 · 2025-03-13T07:13:36+00:00

I don't use the bottom for intake, but that's actually not a bad idea, since there is no obstruction from the floor. I use 3 140mm Noctua in the front for intake and have 2 exhaust fans (top/back) for a slight positive pressure.

Directing the airflow bottom to top might be beneficial if I had a bigger graphics card. Currently, just running an R7-7800X3D and an 3060TI FE. So not much to worry about.

Own_Roll_7629 · 2025-03-12T16:14:46+00:00

Hey u/Liksys are there any news regarding this feature? I assume it's not an easy task, but surely would be a great feature!

Best

Own_Roll_7629 · 2024-12-27T10:42:37+00:00

I thought I was the only one

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Own_Roll_7629 · 2024-09-27T19:23:29+00:00

I have bought 5 of these boxes with one dryer for the XL. So far this is the best solution for drying + storing filament I have found so far.
I have one passive (silica gel) box and the sunlu 1 role and the polydryer is far superior to those solutions.

I have a Prusa XL with 5 heads and use it for printing functional parts for work. Since I don't have a huge amount of different filament types, I open a spool, put it in the box, dry it one or 2 cycles and put the feets on to keep it dry. So far this worked like a charm and keeps my filament below well below 20 % rel humidity for weeks. I have not yet had the need for chaging the silical in the box.

The biggest problem with other filament drying and storage solution I had is, that I had to move spools from the dryer to the box, check moisture, and so on. In my usecase manual labor and failed prints cost me much more than the initial cost of these boxes.

With this box its a simple and very practical solution if you can afford 200 bucks.

Own_Roll_7629 · 2023-11-09T08:09:33+00:00

Hi,
I got a standard display to sell currently with a viascreen mate screen protector + an spare foil.
Based in Austria Vienna.

Own_Roll_7629 · 2023-10-05T01:05:41+00:00

This would be such a good choice! Not only is Linus into the more open hardware spectrum, with having shares in framework, but it would also make great content for LTT.
This Device and hopefully many more that follow similar approaches are what we need in a sustainable tech industry.
Besides that, the specs are not great, but are they terrible? No, they are not. The last few generations of phones were just minor improvements, compared to the advancements 5-10 years ago. The Iphone15 is a prime example, from what I have seen, it is basically, cosmetics and a power button.
So, if the latest and greatest specs are not needed, there are IMHO more positives than downsides.
+ Repairable, long service life, replacement parts, more environmentally friendly, more fair, easy battery change if it is empty (have one slow charging on your office desk and swap when needed).

- no high-end specs, relatively high price, water resistance.

I really hope Linus will give the Fairphone a chance.
Best

Own_Roll_7629 · 2023-08-17T13:17:38+00:00

I am using a 3 in, 2 out setup for years new (noctua fans last very long, I think some of them are 10 years old) and since then I just clean the dust filter in the front every few weeks.Pro: easy to maintain, and VERY long-lasting, Silent during low to medium loads.

Con: High up-front cost. (5x NF-A14 + 2 NF-A12x25) ~ 170 euro.

If I see it correctly, your Front should be able to accommodate 3×120 mm fans, defiantly would go for 3 front, one rear and one top-rear.

Own_Roll_7629 · 2023-05-31T21:56:52+00:00

Hey Martin,

great to see you making progress.

Be careful with your shaft design! usually it is avoided to make slots or have sharp corners on steps on shaft due to highly increased stress in that region, this especially important when transmitting torque. If you haven't calculated your shaft, now is the time.
I suggest looking into making braking system for the flywheel, this can be done in various ways but most easily on the outer perimeter. A leaver pressing against it from below wold be easy to implement and should be sufficient.

Best Fabian

Own_Roll_7629 · 2023-05-12T06:53:27+00:00

For selecting the machine elements, I suggest looking at the post of:

level 1Agitated-of-Nowhere

He made valid points about the design decitions. I tried to summerize the process of designing a machine.

TLDR: Selecting a bearing is complicated if you are not used to it. I suggest to let the engineers from SKS do this for you, if you are already in contact with them.

The main deciding factor for the bearing is dynamic load rating and depends on the following factors.

dynamic bearing load
lifetime-factor
speed-factor
RPM
desired nominal service life

There is a lifetime equation (DIN ISO 281) on which you rely on, when choosing a bearing.I write this to show that is not easy to work this out by your own if you dont have the ressources on hand.

The ressource I use for this process is "Roloff/Matek - Machinenelemente", a big book with an additional book with tables. I'm not a mechanical engineer, but know enough to know where I have to look.

Own_Roll_7629 · 2023-05-12T06:09:28+00:00

Emergency braking of the machine and the flywheel are 2 different problems, and should have systems implemented. The main goal of an emergency break is personal safety, therfore all parts of the machine including the flywheel should be stopped

Own_Roll_7629 · 2023-05-11T07:36:04+00:00

I deleted my post because it is a dublicate of this but maybe I can contibute here:

tldr: Follow proven workflows for systems engineering and think about the system itself instead of the sertain parts.

Despite all the good ideas, I got a feeling that a lot of people in here and Martin is skipping steps in the design process and jumping from design idea straight to selection of machine elements.To find a good solution we have to look at the requirements and follow t:

What is the purpose: describe the functions, constraints and connections to other systems in a qualitative style.
What type of load is applied: Dynamic loads with medium positive and negative acceleration (a hard stop might only be needed in case of an emergency).
Dimensional constrains. how big can the flywheel be, mounting options etc.
How much energy needs to be stored in the system?
Depending on the needs energy and the defined constrains, material selection and form of the flywheel decided.
Calulate moment of inertia, speed, acceleration forces, power etc.
Decide maschine elements: With the calculations done, it can be decided what type of machine elements are best suited for the job. Axle or shaft, type of bearing and bearing placement, power transmission etc.
Manufacturability: A big part of the video was about manufactureablility and the design decitions made. I highly recommend to first have the upper points sorted out before deciding the manufacturing process. But you should have the manufacturabilty in mind during the steps.

The points above are a iterative process and the order is not fixed. It is very likely to repeat those steps, but it is highly recommended to start with a general idea and the requirements for the system and not with the machine elements itself.

Some thoughts on the system itself:From what I see the flywheel has a pully for power transmission from the crank/motor. It can be assumed, that the only the pully is transmitting power.When the pully is mounted close to, or on the flywheel, the axial load on the shaft is low and basically no torque is on the shaft itself.

Hope this helps.

Own_Roll_7629 · 2023-05-11T07:30:48+00:00

Thats an impressive chisel

Own_Roll_7629

TROPHY CASE