What do I need to go with a Pi 4

In message snipped-for-privacy@esprimo.zbmc.eu>, Chris Green snipped-for-privacy@isbd.net writes

Thanks. An interesting looking little beastie, but the only place I could find selling them was Currys, and they appear to be for trade sales only.

Adrian

Thanks.

There appear to be several likely looking cases on Thingiverse (other sites available), so I suspect that I'll download one of those, and if needs be tweak it for my needs.

Adrian

Look on eBay, there's a German company selling refurbished Q957s. The current model is the Q958 (I think), you'll probably find more people selling that.

I'll try and post mine somewhere. Finished it last night,. It's working well with two SSDS and a chip temp of around 65°C-75°C dependent on load.

$ vcgencmd measure_temp temp=68.1'C

Can you tweak STLs?

I have a pi4 2Gb RAM in a closet, running 24/7. The load on it I'd say is low to medium (whatever that means) It polls betfair for odds during horse races as fast as it can when a 'suitable' race is on. That is 1-5 minutes say up to 30 times per day. It inserts that data into a PostgreSQL database and makes graphs ans stats a couple of times per day. It never exceed 50 C so far. I've got historical 'vcgencmd measure_temp' for some years now - once per minute

It is in a flirc case - no fan.

In message <uv8be3$1k8fn$ snipped-for-privacy@dont-email.me, The Natural Philosopher snipped-for-privacy@invalid.invalid writes

Thanks

I found a suitable candidate on printables.com :

which I've modified. I've made the base 4mm thicker, which gives me enough depth to put two countersunk holes in it so I can screw the base down.

Not easily. However, in this case (!), there is the option to download the f3d file which can be uploaded into Fusion360 and then worked on in there.

Pi4, power supply and HDMI lead on order. I was hoping that they would arrive today, but DHL seem to think that they would prefer to spend their day at their local depot.

Adrian

In message snipped-for-privacy@ku.gro.lloiff>, Adrian snipped-for-privacy@ku.gro.lioff> writes

After spending a day at the depot, it was sent out for delivery today. According to the 07:58 email, it should have been with me between 10:19 and 11:19. According to the tracking site, at 10:30 I was the next drop. At 14:20 I gave up waiting and went out. Parcel arrived at 14:40, and was left next to the front door, fortunately not obvious from the road.

Work is now underway to install the software etc. on the new Pi.

Thanks again for all the help.

Adrian

The Pi 4B will definitely throttle with only a ventilated case if it is anything other than sitting idle all the time.

I don't see the point of letting it throttling when an inexpensive fan will keep it at full speed under any load.

---druck

I use this passive heatsink on my pi4s

p.s. disclaimer - no relationship to pihut except as a satisfied customer.

I am not interested in proof by assertion I had mine up to 130% on 'top' and it never made more than 76°C

I question that it will in fact throttle.

Like so much 'everybody knows' when you look at it it is in fact 'everyone believes because people selling fans told them so.

The whole point of ARM is its lower power and lack of need for forced cooling

I sometimes use a small 12V fan on Pi3 or Pi4, running at 5V. It does not "blow", but it "moves air" well h to prevent throttling.

No all 12V fans will work, but if it does, it is silent and with less wear than high RPM fans.

So you were only using 1 and a bit cores, hardly taxing it.

If you do something which uses multiple cores it will.

I'm telling you so, and I'm not selling you a fan, although I do have a bridge going spare if you don't believe that.

That might have been the case for a Pi 1 or 2, 3 and 3+s would throttle if pushed hard enough, 4s and 5s will easily.

---druck

I use the Flirc full body aluminium case for my two Rpi4s, it does not have a ventilator but nicely transports the energy away from the CPU and you can feel that the case gets slightly warm when the Pi is in use. I like it this way because there is one part less that can break in the setup.

-jw-

In message snipped-for-privacy@ku.gro.lloiff>, Adrian snipped-for-privacy@ku.gro.lioff> writes

Noting the discussions elsewhere on the thread, I though the following might be useful. I take various readings every minute including the CPU temperature, the ambient temperature and the CPU loading. Having now had the Pi4 installed in its new home, the following is from the first full 24 hour period (min max mean) :

CPU Temp 36.5 51.1 41.1 Ambient temp 12.7 18.5 15.6 CPU load % 0.00 1.31 0.09

It will be interesting to see how that works out over a longer period.

Performance wise, it is a vast improvement. Prior to the upgrade on matplotlib, I had one job running every 10 minutes, taking 5-6 minutes (11-12 minutes post software upgrade). That now runs in under 1 minute.

Adrian

I don't know what case you are using, but I have tested my geekworm aluminium passive case. It does not throttle using:

stress-ng --cpu 4

Calcs suggest it might throttle on the hottest day of the year, but not normally.

You do know that 'top' won't show throttling? Throttling means the CPU is clocked lower than the maximum frequency to reduce heat generation - top will still show '100%' of CPU (for one core) but that will be 100% of a lower clock speed.

cat /sys/devices/system/cpu/cpu0/cpufreq/scaling_cur_freq

shows you the current clock of CPU core 0 and:

sudo vcgencmd get_throttled

will tell you the throttling status:

#### get_throttled

Returns the throttled state of the system. This is a bit pattern.

| Bit | Meaning | |:---:|---------| | 0 | Under-voltage detected | | 1 | Arm frequency capped | | 2 | Currently throttled | | 3 | Soft temperature limit active | | 16 | Under-voltage has occurred | | 17 | Arm frequency capped has occurred | | 18 | Throttling has occurred | | 19 | Soft temperature limit has occurred

For example if I run 'stress -c 4' then get_throttled gives me: throttled=0xe0008

so the temperature limit is in operation and throttling has occurred in the past. (this Pi4 has cooling, I can't remember but I think there's a heatsink and fan in there)

$ sudo vcgencmd measure_temp temp=84.7'C

so it's up near its thermal limit.

'Everybody knows' because they have evidence, not assertions.

Everyone's been thermally limited for maybe 15 years, it's just that Arm cores have traditionally targeted a lower thermal envelope in devices where forced air cooling isn't an option. The way this works is that CPUs work until they hit their thermal envelope and then throttle. No popular application processor for maybe a couple of decades has been able to power all the silicon at once to max performance and stay within the thermal budget.

Theo

I think this thread is lacking precise, clear language, and people are making false comparisons. Talking about ventilated cases is confusing, I don't know what a thermal budget is.

There are four points:

2) With no heatsink at all the rPi4 will throttle under compute intensive workloads.

4) Most of us don't use the rPi4 for continuous compute intensive tasks.

There, that should make everyone happy :-)

Mine runs hot because there is a TV hat bolted on top. And a SSD drive bolted underneath

that pushes up the case internals way more than the Pi does But it is still happy and unthrottled