cpu governer leaves v3d only at 600mhz at one pi4 while going tot 815mhz on another pi4

[mitu]

@Riverstorm said in cpu governer leaves v3d only at 600mhz at one pi4 while going tot 815mhz on another pi4:

I originally had my over_voltage set to 5 but found if the power isn't "smooth" at your location it may crash. I haven't had a single crash at 6 and it shouldn't void the warranty unless used in conjunction with force_turbo, the heat jump is marginal.

The Pi4 doesn't have a 'warranty' bit, any over-clocking configuration is not recorded anymore - as it was on previous models when force_turbo/over_voltage were set.

[Riverstorm]

@mitu said in cpu governer leaves v3d only at 600mhz at one pi4 while going tot 815mhz on another pi4:

The Pi4 doesn't have a 'warranty' bit, any over-clocking configuration is not recorded anymore - as it was on previous models when force_turbo/over_voltage were set.

Hey @mitu ok, thanks for the information. Is that a recent firmware change or does their website need an update? This is what they have current and several references on the forums to the warranty bit, revision tables for all the versions, etc. on the Pi 4 as recent as April. I couldn't find anything different from what is posted below.

NOTE: Setting any overclocking parameters to values other than those used by raspi-config may set a permanent bit within the SoC, making it possible to detect that your Pi has been overclocked. The specific circumstances where the overclock bit is set are if force_turbo is set to 1 and any of the over_voltage_ options are set to a value > 0. See the blog post on Turbo Mode for more information. Pi 4 overclocking options may be subject to change in the future.*

Hi there i just overlocked my pi 4 via the config and overlolted it to 6.
How do i check the warranty bit and is the warranty now voided?
That's c03112 4B 1.2 4GB Sony UK

It isn't. The revision would show as 2c03112 if the warranty void bit was set.

[mitu]

@Riverstorm said in cpu governer leaves v3d only at 600mhz at one pi4 while going tot 815mhz on another pi4:

Hey @mitu ok, thanks for the information. Is that a recent firmware change or does their website need an update? This is what they have current and several references on the forums to the warranty bit, revision tables for all the versions, etc. on the Pi 4 as recent as April. I couldn't find anything different from what is posted below.

See this post by a RPT engineer:

The "warranty" bit was added as a way of pacifying suppliers who were nervous that allowing overclock may result in a large number of dead Pi's being returned. But since the first Pi was released we've never seen a Pi that appears to have died through overclocking.

We don't even set the bit on Pi 4, so feel free to experiment. Obviously too high an overclock may make a Pi unstable and crash.
Don't do it on a Pi with valuable data on it without a backup.

The benefits of overclocking newer Pi models is much less than on the original Pi 1, as the default speed is so much greater.

[akamming]

@Riverstorm said in cpu governer leaves v3d only at 600mhz at one pi4 while going tot 815mhz on another pi4:

tx for all the useful info. here's a reaction.

From what you're saying it seems it ignores up_threshold when set to performance but honors it with on-demand.

Yep, and that's expected behaviour and the reason why i used runcommand to set the governer to performance. I noticed btw that performance is slightly better whith the governance set to performance. Although both pi's now act the same (the difference was the up_treshold setting). They both sometime dropped the v3d clock back to 600. Where in performance it stays at 815. and apparently this is need for n64 and psp emulation, cause i have a slightly better fps when the clock runs a 815. and since i now don't use the ondemand governer when running the emulators, i don't have to play around with stuff like sampling rate, sampling down factor, etc...

The other thing worth testing when overclocking, that sounds contrary, is idling your overclock. I found certain overclocks will lockup when idling or doing simple attract mode loops in the most basic arcade games.

i did not do a specific test, but since the pi is built into an arcade cabinet, most of it's time it's idling without issues (i would expect so, cause the the clock drops down to normal rates when the cpu/gpu is not used). Do you have a specific game in mind which crashes in attract mode with unstable overclock? I haven't seen this behaviour yet…

I was able to easily achieve a stable 2.1GHz (heavily tested across days) once I removed gpu_freq. I was not able to achieve a stable overclock at 2.147 (the theoretical max with the latest firmware) but 2.1 was no problem. I don't know but I would assume the v3d_freq will override the gpu_freq since it is in direct conflict with the more precise setting vs. the blanket setting but I would just remove it.

2.1 GHz is almost stable, but sometimes gives freezes or reboots, so i went down to 2.0Ghz (no problems since). according to the docs i found gpu_freq should not be set on a pi 4, cause this might make it unbootable, but i accidentally did it and found out that on a pi4 this sets the default clock speeds for h264, isp van v3d freqs. which can be overruled by the indivudeal settings (so that's why i have gpu_freq=750, v3d_freq=815). i use hdmi_enable_4kp60 to boost the core freq.

i know i need more cooling if my goal was to use as much processing power as possible. however i don't like moving parts so try to avoid them. And with passive cooling, even with overclock temperatures never reach the point where the system starts to throttle when playing retro games.

[akamming]

@mitu said in cpu governer leaves v3d only at 600mhz at one pi4 while going tot 815mhz on another pi4:

@Riverstorm said in cpu governer leaves v3d only at 600mhz at one pi4 while going tot 815mhz on another pi4:

Hey @mitu ok, thanks for the information. Is that a recent firmware change or does their website need an update? This is what they have current and several references on the forums to the warranty bit, revision tables for all the versions, etc. on the Pi 4 as recent as April. I couldn't find anything different from what is posted below.

See this post by a RPT engineer:

The "warranty" bit was added as a way of pacifying suppliers who were nervous that allowing overclock may result in a large number of dead Pi's being returned. But since the first Pi was released we've never seen a Pi that appears to have died through overclocking.

We don't even set the bit on Pi 4, so feel free to experiment. Obviously too high an overclock may make a Pi unstable and crash.
Don't do it on a Pi with valuable data on it without a backup.

The benefits of overclocking newer Pi models is much less than on the original Pi 1, as the default speed is so much greater.

That's interesting! this would imply i could try to overclock more by increasing the voltage without reducing the lifespan or limiting the warranty. Has anyone alread tried if this is really the case? (set force_turbo and over_voltage>6 and then check the warranty bit?)

[Riverstorm]

@mitu - That's very interesting, that kind of changes the ball game a little and the thinking on overclocking. It's only a small bump in power going to 8 (the max value) using force_turbo but it may help stabilize a slightly higher overclock.

I'm a little surprised as it implies for the most part you can't damage the Pi or warranty from overclocking but I suppose they still have controls in place with a cap at 1.4V. If you can zip the temp straight up fast enough through high voltage maybe but I don't know. I'll have to let that soak in as that's just interesting information.

On the inverse you can set a bit to lock the Pi so you can't overvolt at all.

It's similar to Intel's K line of chips. You basically pay a higher price I suspect to offset the cost to the company for a higher burn percentage on unlocked chips.

It's not much different than Alienware or Falcon that do a 3 day burn-in test that voids even the Intel warranty but they cover it for the life and then an additional year or two. Falcon's come at a very premium price though with those custom paint jobs.

Of this beauty a Silverdraft Demon coming in at a hefty $49,500! You need this for proper MAME gaming! ;)

@akamming - I never worried much about shortening the lifespan of the Pi. I've pretty much have "junked" every generation of Pi long before it ever had a chance to burn out.

I honestly think as hard as I've been running my Pi 4's they will still run for years and years with a proper cooling solution. The testing is such a small part of their life. If you keep it cool enough I would even venture it will last just as long. Heat aside I have no idea if slightly higher voltage through capacitors and other components shortens their life.

One thing I found the hard way is always overclock test with a backup image. Each lockup slowly corrupts the image, even though it still boots fine. I thought the image was clean until I used pishrink. It will not compress down properly with any errors in the image file structure. In fact it tries to correct them and fails more times than not.

With performance it's going to bump to the highest frequency based on the up_threshold within the limits of the min/max values and hold it there based on the sampling_rate.

On-demand will start adjusting the frequency based on the up_threshold and load (estimation) but within the limits of the min/max values and hold it there based on the sampling_rate.

powersave will operate on the opposite end making frequency adjustments based on the min values set.

It makes sense what you're saying about better performance. Basically performance will peg at the set frequency but on-demand will bump it up and down based on "load sampling" and not necessarily set it to the max frequency.

If you're Pi is in one location I think you could build a sufficient passive solution for higher overclocks. It might be a bit larger than average but it wouldn't have any moving parts!

[mitu]

@Riverstorm said in cpu governer leaves v3d only at 600mhz at one pi4 while going tot 815mhz on another pi4:

Of this beauty a Silverdraft Demon coming in at a hefty $49,500! You need this for proper MAME gaming! ;)

Actually, if you closely look at the Q&A section, they don't recommend it for gaming. Plus, only 198Gb memory at this price and no SD card slot ? C'mon.

We would not suggest this super high end gaming workstation for gaming. As the processor and multiple video cards of this type are not geared toward gaming.

[Riverstorm]

@mitu - Well shoot! No gaming and you would think you could get a SD card slot (or dare I say, two!) for that price. I knew it was to good to be true at 50 grand.

198Gb...it's impressive, that's almost as much RAM as our boot drives on M.2 SSD's.

Kind of off topic but that's the other thing Intel is doing that I don't care for are the newer KF chips. Basically they have the unlocked multiplier (K--as always) but the (F) means no integrated graphics. There's nothing like having a way to selling defunct chips.

They failed QC for one reason or another with the integrated graphics but they still sell them at almost the same premium price as the regular K chips that have integrated graphics.

Companies like Dell are picking them up (I'm sure at a discount) and re-purposing them in their Alienware line.

Anyway a minor rant for an otherwise great gaming rig!

[Clyde]

@Riverstorm said in cpu governer leaves v3d only at 600mhz at one pi4 while going tot 815mhz on another pi4:

Of this beauty a Silverdraft Demon coming in at a hefty $49,500! You need this for proper MAME gaming! ;)

You could get approx. 1,400 2GB Pi 4 with collectively 2,800 GB of RAM for that, or 660 8GB Pi 4 with 5,280 GB total RAM, and then build a RPi cluster:

(Yes, there are newer videos of RPi clusters, but this is the most beautiful that I know of. 🤩 )

That said, actually I would very much like to see how such a cluster would fare against the Silverdraft Demon. 👹

[Riverstorm]

You could get approx. 1,400 2GB Pi 4 with collectively 2,800 GB of RAM for that, or 660 8GB Pi 4 with 5,280 GB total RAM, and then build a RPi cluster:

Whew, that's going to take up it's fair share of space for the Pi's alone. Minus racks, cooling, power, etc. for the Pi's I used the bigger number just for fun.

Pi dimensions - 56.5 x 85.6 x 11 mm = 53.2004 cm^3

53.2004 cm^3 x 1400 = 74,480.56 cm^3

So if those calculations are correct you're going to need 74,481 cubic centimeters which is roughly 745 cubic meters for the Pi's alone. You're gonna need a fair sized room!

OR

The Silverdraft Demon - 43.18 x 43.18 x 27.94 cm

[Riverstorm]

Don't forget you might need a bit of extra room, a mm or two for the SD card protruding from the side!

[mitu]

@Riverstorm I think you can netboot the Pi4 without the sdcard, since now the bootloader is in the EEPROM, so you don't need any storage for the systems.

[Riverstorm]

@mitu - I like the way you're thinking, with a bit of creative engineering we've already reduced the footprint! I think we're on to something here... ;p

[Clyde]

@Riverstorm said in cpu governer leaves v3d only at 600mhz at one pi4 while going tot 815mhz on another pi4:

So if those calculations are correct you're going to need 74,481 cubic centimeters which is roughly 745 cubic meters for the Pi's alone. You're gonna need a fair sized room!

That's true, but a) it's cool, and b) with a little work on the interior design, you may be able to actually live in it! 🤓

(The video's creator already had shrunk the power supply quite good by serialising it.)

@Riverstorm said in cpu governer leaves v3d only at 600mhz at one pi4 while going tot 815mhz on another pi4:

@mitu - I like the way you're thinking

I wanted to say that to both of you guys. One thing that remains is a proper name. Off the top of my head, the rather unspectacular "MegaPi" came up, quickly followed by "ClusterF*ck". 😉