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Silicon lottery.

Now that the Raspberry Pi 5s been readily available (at least in most regions) for a few months, more people started messing with clocks, trying to get the most speed possible out of their Pi 5s.

Unlike the Pi 4, the Pi 5 is typically comfortable at 2.6 or even 2.8 GHz, and some Pi 5s can hit 3.0 GHz (but no higher—more on why tomorrow well... this limit may be able to be lifted).

After some testing, I found the default 2.4 GHz clock on the Pi 5 is pretty much the efficiency sweet spot, and after a lot more testing recently, I can confirm that's still the case, testing a number of Pi 5 samples.

I install a lot of Drupal sites day to day, especially when I'm doing dev work.

In the course of doing that, sometimes I'll be working on infrastructure—whether that's an Ansible playbook to configure a Docker container, or testing something on a fresh server or VM.

In any case, I run into the following error every so often in my Nginx error.log:

"php-fpm" nginx Error: Undefined constant PDO::MYSQL_ATTR_USE_BUFFERED_QUERY

The funny thing is, I don't have that error when I'm running CLI commands, like vendor/bin/drush, and can even install and manage the Drupal site and database on the CLI.

The problem, in my case, was that I had applied php-fpm configs using Ansible, but in my playbook I hadn't restarted php-fpm (in my case, on Ubuntu 22.04, php8.3-fpm) after doing so. So FPM was running with outdated config and didn't know that the MySQL/MariaDB drivers were even present on the system.

Old advice for setting a Raspberry Pi IP address to a static IP on the Pi itself said to edit the /etc/dhcpcd.conf file, and add it there.

But on Raspberry Pi OS 12 and later, dhcpcd is no longer used, everything goes through Network Manager, which is configured via nmcli or nmtui. If you're booting into the Pi OS desktop environment, editing the IP settings there is pretty easy.

But setting a static IP via the command line is a little different.

First, get the interface information—you can get a list of all interfaces with nmcli device status:

$ nmcli device status
DEVICE         TYPE      STATE                   CONNECTION         
eth0           ethernet  connected               Wired connection 1 
lo             loopback  connected (externally)  lo                 
wlan0          wifi      disconnected            --                 

In my case, I want to set an IP on eth0, the built-in Ethernet.

There are about a dozen ways to get files to and from an older Mac like my PowerBook 3400c, but right now (at least until I figure out a good way to get my NAS -> an AppleTalk server -> 3400c working), my preferred method is via a CF card—I pop the CF card into a CF-to-PCMCIA adapter, then insert that into one of my PowerBook 3400's PC card slots, and bingo: removable flash storage on a 1990s laptop!

I still have a few CF cards kicking around (I used them with my old Nikon D700 camera), and you can buy a 4GB SanDisk Ultra CF card new from Amazon still—albeit for the price of $35... Sometimes the smaller/older cards work better with old Macs, and most of the files I deal with are well under a few MB anyways.

I've been building out a new Arm-based NAS using ASRock Rack's new 'Deep Micro ATX' motherboard for Ampere Altra and Altra Max CPUs.

I posted about the hardware earlier, in Building an efficient server-grade Arm NAS. Go check that out if you want details on the specific hardware in this setup.

But at the end of the build, I installed Rocky Linux, and found the power consumption to be a bit higher than expected—over 150W at idle!

As it turns out, the NAS must've been doing something when I took that initial measurement, because after monitoring it for a few more days, the normal idle power usage was around 123W instead.

tl;dr: 52Pi and Seeed Studio's water cooling solution for the Raspberry Pi 5 can be fun, and works better than any other solution—but at a steep price, and with a number of annoying quirks.

A few months ago, 52Pi reached out and asked if they could send a new water cooling kit they were working on for the Raspberry Pi 5. At the time, the hope was we could figure out a way to get very high overclock with adequate cooling.

Unfortunately—for reasons I'll explore more soon—the Pi 5 can't overclock beyond 3.0 GHz (it's not physically possible). Some of why is explained in my blog post Overclocking and Underclocking the Raspberry Pi 5.

But water cooling is still fun, and the product is in production now, so I figured I'd still give it a fair shot, and see if I thought it might be worth buying for certain niche use cases.