Pi4 8GB cannot overclock gpu_freq at all!

tomstephens89 · March 27, 2022 at 9:39 AM

Hi all, I am running LibreElec on an 8GB Raspberry Pi 4 inside an Argon Onev2 case with the fan script configured and working.

I know its wasted on LibreElec/Kodi but being a full time tech, I have to push performance just for kicks. As such I am trying to overclock my Pi4 to make a 'super' media center Pi. Even in stock configuration the thing doesn't appear to break a sweat, very impressive.

However I have a 'problem' and I think there's something strange going on:

I am able to overclock the CPU, 'arm_freq' to 2Ghz and beyond with no problems at all, with an over_voltage set to 6. Haven't tried to lower the voltage, but hey ho...

Logical next step is to bump the GPU frequency up a little, however if I even attempt to bump 'gpu_freq' up a mere 50Mhz to 550 then when I try to playback a h265 file, I will immediately lose video output but the OS doesn't crash and the Pi is still reachable via SSH and responds to commands so I can revert and reboot etc...

I have tried an over_voltage setting upto 12 which made no difference.

What could be going on here? Almost every Pi4 user out there reports being able to achieve over 700Mhz on the GPU and I can't even touch mine, yet I can hit 2.147Ghz and probably more on the arm_freq.

Because I am losing video and not crashing the whole Pi, even when just tickling the GPU frequency, I suspect I need to force another setting to do with HDMI out or something.

Does anyone have any experience with similar?

Heres my config.txt, GPU overclock commented out as it doesn't work. Not 550, not 600, not 650 etc.... Just a loss of video, no full OS crash.

Code

# Default GPU memory split, 76MB are needed for H264 decoder
gpu_mem=128

# Don't send initial active source message.
# Avoids bringing CEC (enabled TV) out of standby and channel switch when
# rebooting.
hdmi_ignore_cec_init=1

################################################################################
# Include distribution specific config file if it exists.
################################################################################
[all]
include distroconfig.txt

# uncomment to enable infrared remote recevier connected to GPIO 18
#dtoverlay=gpio-ir,gpio_pin=18
dtparam=i2c=on
enable_uart=1
#current_limit_override=1
over_voltage=6
force_turbo=1
arm_freq=1800
#gpu_freq=600

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Heres the results of some playback on temps, showing everything is well under control. The argon cools passively until it hits 55c which is where I have the fan set to come on.

30 mins 4k h265 playback:

Code

LibreELEC:~ # bcmstat.sh
  Config: v0.5.5, args "", priority lowest (+19)
   Board: 4 x  cores available, ondemand governor (Pi4 Model B rev 1.4, BCM2838 SoC with 8GB RAM by Sony UK)
  Memory: 1024MB (split 896MB ARM, 128MB GPU)
HW Block: |   ARM   |  Core  |  H264  |    SDRAM    |
Min Freq: | 1800MHz | 500MHz |   0MHz |   3180MHz   |
Max Freq: | 1800MHz | 500MHz | 500MHz |   3180MHz   |
Voltages: |        +6, 1.0000V        | +0, 1.2000V |
   Other: temp_limit=85, force_turbo=1
Firmware: Mar 1 2022 14:22:32, version 969fb9b1521fc7ac2b88b15a3a9e942da7678c4d (clean) (release) (start_x)
  Codecs: H264 MJPG PCM
  Booted: Sun Mar 27 08:35:56 2022

Time         ARM    Core    H264 Core Temp (Max)  IRQ/s      RX B/s      TX B/s
======== ======= ======= ======= =============== ====== =========== ===========
09:00:32 1800Mhz  500Mhz    0Mhz 44.30C (45.76C)  1,121         296         113
09:00:34 1800Mhz  500Mhz    0Mhz 44.30C (45.76C)  1,125         334         113
09:00:36 1800Mhz  500Mhz    0Mhz 44.79C (45.76C)  1,086         177         113
09:00:39 1800Mhz  500Mhz    0Mhz 44.30C (45.76C)  1,118         477         113

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30 mins 1080p h264 playback:

Code

LibreELEC:~ # bcmstat.sh
  Config: v0.5.5, args "", priority lowest (+19)
   Board: 4 x  cores available, ondemand governor (Pi4 Model B rev 1.4, BCM2838 SoC with 8GB RAM by Sony UK)
  Memory: 1024MB (split 896MB ARM, 128MB GPU)
HW Block: |   ARM   |  Core  |  H264  |    SDRAM    |
Min Freq: | 1800MHz | 500MHz |   0MHz |   3180MHz   |
Max Freq: | 1800MHz | 500MHz | 500MHz |   3180MHz   |
Voltages: |        +6, 1.0000V        | +0, 1.2000V |
   Other: temp_limit=85, force_turbo=1
Firmware: Mar 1 2022 14:22:32, version 969fb9b1521fc7ac2b88b15a3a9e942da7678c4d (clean) (release) (start_x)
  Codecs: H264 MJPG PCM
  Booted: Sun Mar 27 08:35:56 2022

Time         ARM    Core    H264 Core Temp (Max)  IRQ/s      RX B/s      TX B/s
======== ======= ======= ======= =============== ====== =========== ===========
09:21:14 1800Mhz  500Mhz  500Mhz 45.76C (45.76C)  4,544           0           0
09:21:16 1800Mhz  500Mhz  500Mhz 44.79C (45.76C)  1,073         483         276
09:21:18 1800Mhz  500Mhz  500Mhz 45.28C (45.76C)  1,018         150         247
09:21:20 1800Mhz  500Mhz  500Mhz 45.28C (45.76C)  1,082         178         113
09:21:22 1800Mhz  500Mhz  500Mhz 45.76C (45.76C)  1,052         284         113

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**popcornmix** · March 27, 2022 at 11:35 AM

Quote from tomstephens89

Logical next step is to bump the GPU frequency up a little, however if I even attempt to bump 'gpu_freq' up a mere 50Mhz to 550 then when I try to playback a h265 file, I will immediately lose video output but the OS doesn't crash and the Pi is still reachable via SSH and responds to commands so I can revert and reboot etc..

Disable "adjust refresh rate to match framerate" and I suspect you'll get a picture.

Your overclock is having the same effect as "hdmi_enable_4kp60=1" and something isn't supporting that.

Do you have another hdmi cable or 4k display to test with?

tomstephens89 · March 27, 2022 at 1:58 PM

Quote from popcornmix

Disable "adjust refresh rate to match framerate" and I suspect you'll get a picture.
Your overclock is having the same effect as "hdmi_enable_4kp60=1" and something isn't supporting that.
Do you have another hdmi cable or 4k display to test with?

Thanks for the reply. Where do I find that setting? If its within KODI and is Settings > Player > Videos 'Adjust display refresh rate' then its already off.

I don't see "adjust refresh rate to match framerate" anywhere.

**popcornmix** · March 27, 2022 at 4:25 PM

That's the setting. Post a debug enable log when playing a problematic video.

tomstephens89 · March 27, 2022 at 5:18 PM

Quote from popcornmix

That's the setting. Post a debug enable log when playing a problematic video.

Where’s the particular debug log setting and where will the file be?

**Da Flex** · March 28, 2022 at 7:37 PM

Quote from tomstephens89

Where’s the particular debug log setting and where will the file be?

Please provide a full debug log.

How to post a log (wiki)

1. Enable debugging in Settings>System Settings>Logging
2. Restart Kodi
3. Replicate the problem
4. Generate a log URL (do not post/upload logs to the forum)

use "Settings > LibreELEC > System > Paste system logs" or run "pastekodi" over SSH, then post the URL link

Pretoriano · March 28, 2022 at 8:34 PM

Tried to reproduce this on my RPi4, but i couldn't.

LibreELEC - LE 10.2

Raspberry - RPi4 8GB rev. 1.4

Overclock - CPU 1800MHz GPU 600 Mhz

Tested :

- inputstream.adaptive VP9 (SW) - Netflix stream

- drmprime HEVC (HW) - local video

- ff-h264 drm_prime (HW) - local video

bcmstat - ovorclock is working

Code

22:14:21 1800Mhz  600Mhz    0Mhz 33.10C (36.51C) 12,106   4,546,123     101,927
22:14:23 1800Mhz  600Mhz    0Mhz 33.10C (36.51C) 13,138   4,985,402     113,389
22:14:25 1800Mhz  600Mhz    0Mhz 34.08C (36.51C) 14,350   5,559,116     125,401
22:14:27  900Mhz  499Mhz    0Mhz 33.10C (36.51C) 11,662   5,026,492     100,140
22:14:29  900Mhz  499Mhz    0Mhz 32.62C (36.51C) 10,341   4,619,576      82,231^C
Peak Values: IRQ: 17612, RX: 7546972, TX: 158784

config.txt

Code

# SPDX-License-Identifier: GPL-2.0-or-later
# Copyright (C) 2009-2014 Stephan Raue (stephan@openelec.tv)
# Copyright (C) 2016-present Team LibreELEC (https://libreelec.tv)
################################################################################
# Bootloader configuration
# config.txt version v1 (do not remove or change this line!)
################################################################################
# For more options and information see
# http://rpf.io/configtxt
################################################################################

# Default GPU memory split, 76MB are needed for H264 decoder
gpu_mem=128

# Don't send initial active source message.
# Avoids bringing CEC (enabled TV) out of standby and channel switch when
# rebooting.
hdmi_ignore_cec_init=1

################################################################################
# Include distribution specific config file if it exists.
################################################################################
[all]
include distroconfig.txt

# uncomment to enable infrared remote recevier connected to GPIO 18
#dtoverlay=gpio-ir,gpio_pin=18
dtoverlay=i2c-rtc,ds3231
initramfs edid.cpio
arm_b00st=1
gpu_freq=600

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The forum complained about a censored word (really?) so on arm_b00st replace 00 with oo

**Da Flex** · March 28, 2022 at 8:54 PM

Quote from Pretoriano

The forum complained about a censored word (really?) so on arm_b00st replace 00 with oo

Sorry. I've sent a request to the admin to remove this word from blacklist.

tomstephens89 · March 30, 2022 at 6:57 PM

See debug log here:

http://ix.io/3TRK

Attempted to playback but lost video out at 18:25 ish.

Noticed this at end of log:

Code

2022-03-30 18:50:27.559 T:1028    DEBUG <general>: ------ Window Deinit (Home.xml) ------
2022-03-30 18:50:27.559 T:1028    DEBUG <general>: FreeVisualisation() done
2022-03-30 18:50:27.560 T:1028    DEBUG <general>: ------ Window Init (VideoFullScreen.xml) ------
2022-03-30 18:50:27.560 T:1028     INFO <general>: Loading skin file: VideoFullScreen.xml, load type: KEEP_IN_MEMORY
2022-03-30 18:50:27.561 T:1068    DEBUG <general>: ffmpeg[0x2d75f88X]: [image2] Custom AVIOContext makes no sense and will be ignored with AVFMT_NOFIL                                                             E format.
2022-03-30 18:50:27.572 T:1048    DEBUG <general>: OnAVStarted: CApplication::OnAVStarted
2022-03-30 18:50:27.574 T:1028    DEBUG <general>: CDRMUtils::DrmFbDestroyCallback - removing framebuffer: 258
2022-03-30 18:50:27.575 T:1044    DEBUG <general>: OnAVChange: CApplication::OnAVChange
2022-03-30 18:50:27.597 T:1028    DEBUG <general>: CDRMUtils::DrmFbDestroyCallback - removing framebuffer: 259
2022-03-30 18:50:27.623 T:1028    DEBUG <general>: ------ Window Deinit (DialogBusy.xml) ------
2022-03-30 18:50:27.653 T:1038    DEBUG <general>: ActiveAE::SyncStream - average error of 1.485731, start adjusting
2022-03-30 18:50:27.653 T:1038    DEBUG <general>: ActiveAE::SyncStream - average error 0.485731 below threshold of 30.000000
2022-03-30 18:50:28.654 T:1177    DEBUG <general>: CDVDClock::ErrorAdjust - CVideoPlayerAudio::OutputPacket - error:-29999.656515, adjusted:-29999.656                                                             515
2022-03-30 18:50:32.525 T:1176    DEBUG <general>: CPtsTracker: detected pattern of length 1: 41708.33, frameduration: 41708.333333

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tomstephens89 · April 3, 2022 at 7:00 AM

Is anyone able to help? Do the logs reveal anything?

Pretoriano · April 3, 2022 at 8:34 AM

Can you provide a sample from the video that it's causing this?

Also, i would try with the RPi out of the Argon case, just to make sure that the case is not part of the equation.

tomstephens89 · April 3, 2022 at 11:24 AM

Quote from Pretoriano

Can you provide a sample from the video that it's causing this?
Also, i would try with the RPi out of the Argon case, just to make sure that the case is not part of the equation.

It happens with multiple videos. But particularly H265 I think.

I also happens outside of the case.