Power Management – Screen is suddenly locked

In Ubuntu 19.10, the screen saver is not activated, and it was only activated today when it suddenly locked itself after about thirty seconds and my password was required to log in again. I checked the power and screen settings and they are the same as they are with nothing I can find to explain that. In the meantime, there were no system updates and it was just started out of the blue. Any ideas, what could have happened and how to stop it?

Is there a power bank that works flawlessly with the MacBook Pro (15 inches, 2019)?

The MacBook charges anything connected to a USB-C cable.

The Apple Charger for the 15-inch MacBook Pro charges with 87 watts. Anything lower will work too, but it will charge slower. I would look for something with a power of 60 watts or at least 45 watts. I think something like that would be painfully slow.

Power storms Power storms from x to n

Power Storms How can I get the math to compute a power tower for a series of numbers instead of writing bones? Mahematica performs the iterative calculation.

     cal= 99^2^3^-----1000  

How can you get math to write it and calculate it?

I understand that the actual calculation can lead to a memory overflow, which can also help me

dnd 3.5e – What power / spell / skill will let you know if you violate a vow / rule of your god as a free act?

I build a D & D 3.5e clergyman in the monastery with a vow of poverty and the vow of peace. In the last two weeks, I've come across a character ability (an ability, a talent, a spell, an alternate class function, a domain skill, or something else) that had the following wording:

as a free act, you can consult your intuition and know if something is in tune with your God's will (or make a vow, I'm not sure what the benefit is)

I explicitly recall that this was a free action that allowed you to check the status of a contemplated action. But I spent 3 hours searching through the book of sublime deeds, the player's manual, and Google, and can not find it.

Character Creation – What 3.5e power / spell / ability does you know if you are breaking a vow / the rules of your god as a free action?

I build a D & D 3.5e clergyman in the monastery with a vow of poverty and the vow of peace. In the last two weeks, I've come across a character ability (an ability, a talent, a spell, an alternate class function, a domain skill, or something else) that had the following wording:

as a free act, you can consult your intuition and know if something is in tune with your God's will (or make a vow, I'm not sure what the benefit is)

I explicitly recall that this was a free action that allowed you to check the status of a contemplated action. But I spent 3 hours searching through the book of sublime deeds, the player's manual, and Google, and can not find it.

From Camera Flash – Portable Mini Studio and Power Management

To improve my portraits, I invested a few months earlier in two flash units, two radio receivers and a radio transmitter. For all this I need 2 * 4 + 2 * 2 + 2 = 14 batteries (eneloop) for the setup to work, and 10 more to replace broken batteries during the recording session (about 2-3 hours). After the shooting I have to charge 24 batteries, which is getting boring, but still handy.

Now I want to add a third flash (and its radio receiver) to have more lighting configuration options. There are 10 more batteries included in the equation.

I also have the project to add small LED panels near the flashes to provide a constant light source. This will help me to better visualize the effect each flash creates. With 2 to 4 batteries per LED display, 12 to 24 additional batteries are added to my collection (considering backup batteries).

As you can imagine, the administration of about 50 batteries is time consuming and probably quite crazy.

I wonder if I could replace the flash batteries and LED panel batteries with a regular power bank (this leaves me with the 8 batteries needed by my 1 radio transmitter and 3 radio receivers).

My analysis of the situation: Each flash requires 4 AA batteries. 1 AA battery is 2500mAh / 1.2V, so a total of about 5V and 10000mAh. Many power banks could supply 5 V with a capacity of over 10000 mAh. The main problem is probably ampere and cycle time: The flash needs about 5-6 amps to have a correct recycling time (about 3 seconds) so the power bank has to have a power of about 25W. According to a brief market overview, most cheap power banks only have a power of 5 to 10 W, but some boost 45 to 60 W (5 V).
For example, Xiaomi says one of his 20000 mAh power bank models can deliver 5V / 5.4A (using his 3 outputs), just over 25W (about $ 50).

Can I use a standard (and inexpensive) USB power bank to optimize power management? Are there any other (cheap) alternatives? How do you do that?

I looked at "serious" power banks (for example Godox Propac), but they are a bit expensive and heavy.

In terms of possible DIY solutions and my experience with electronics, it has been a couple of years since I soldered anything to a board, but I could probably do it.

An important limitation is a "portable" mini-studio. I would like to be able to carry it around in two (big) bags.

Thank you in advance.

Motherboard – Constant restarts. Did I break the second power supply in two weeks?

I was unlucky with my newly built PC, which I only had two weeks ago. It worked well in the first week. Then it was restarted at random (it was not heavily used) and rebooted every few seconds from that point on, usually before the Windows load was completed, sometimes already on the login screen.

In other ways, I've ruled out a software issue and issues with most components (see below). After delimiting the options on the motherboard, CPU, and power supply, I was convinced that it had to be a problem with the motherboard and replaced it (for an identical model): it did not matter. So next I changed the power supply (a completely different brand). Bingo! The PC booted well and worked flawlessly, I managed to play for several hours. But only for 2 days: Then the same happened: A random restart, which now takes place every few seconds.

I do not really know what to think about it:

  1. Was this really the faulty power supply, and broke the second power supply in just a few days?
  2. Was that Not a power supply problem at the beginning?

For both options I have to ask some questions:

  1. If the second power supply broke down in a few days, why then? There certainly has to be something, either on the PC or from the outside, that destroys the power supplies. Could this be a problem with the circuits of the house? But the power outlet is wired correctly (with a little tester tested), the PC is plugged into a surge-protected extension cable, and none of my other electronics ever had a problem. Even if something is wrong with the power supply, how likely is it to cause the same symptoms in power supplies of different brands (Corsair and EVGA)?
  2. If the problem is not the power supplyWhy did the replacement of the power supply make a difference for the two days when everything was fine? Could this really be a problem with the CPU, the only component I have not ruled out? Or did I miss something earlier?

Both options sound illogical to me at the same time … I was hoping that someone here could point me in the right direction.

Exclude components

A detailed description of what I have tried so far, for the sake of completeness:

  1. Software and SSD: The problem also occurs when booting from a USB flash drive containing Ubuntu or the Windows Installer installed on it. Even if the SSD is physically removed.
  2. memory: I have no spare memory for testing, but the problem still exists if one of the two sticks is removed. I also ran MemTest86 for 10 hours, and found no problems (the problem occurs within seconds during normal operation).
  3. graphic card: I bought a cheap used card to test it with the same issue.
  4. overheating: I can see all the temperature readings in the BIOS, they are ok. Reboots occur immediately after the first time the PC is turned on in one day.
  5. motherboard: I have replaced it: unnecessarily, as it turned out, the same problem happened immediately with the replacement.
  6. central processor: Not completely excluded, but probably no problem. MemTest86 ran on all its cores, suggesting that no one is broken. As far as I know, the PC with a deep-fried CPU would not turn on at all.

One reason I did not initially suspect the PSU was the fact that when you ran MemTest86 or some of the other utilities I found on the Ultimate Boot CD, no restarts were done. If the PSU was a problem, should not it make any difference what software was running on the PC? Even if a CPU stress test was performed that I believe would consume a lot of power from the power supply, it did not cause a reboot. For a similar reason, I even thought at some point that the video card is a likely culprit: what all the software that triggers the reboot (Windows, Ubuntu USB key, Windows installation USB stick) has in common is that they have a GUI while the test applications are running in a simple character output. But replacing the card with the one I got for £ 8 on Ebay proved it was not a GPU problem.

Can someone make sense of it?

Power Consumption – Is there a way to access hard drives while the computer is idle?

As the title implies, with hardware (apart from a NAS) there is even a way to access hard disks while the computer is in a power saving mode such as the power saving mode (except for WOL).

Such as; Log on to a network drive on the computer and boot to access data without the computer leaving sleep mode?

Thank you very much