Radeon APU - HD 7660D - output to displayport off pitch / speed

Issues related to hardware problems
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Moschops
Posts: 2
Joined: 2018/12/20 17:29:49

Radeon APU - HD 7660D - output to displayport off pitch / speed

Post by Moschops » 2018/12/20 18:15:00

The motherboard: ASUS F285A - (something).
The CPU /APU: A10-5800K quad core with Radeon HD7660D.
16 GB ram DDR 2133 I think.
OS: Using the latest updated version of Centos 7.x.

Setup: all my computers/workstations were configured to use displayport into a 4k capable kvm switch. Currently using an ASUS monitor capable of 2560 x 1440. In the near future would like to be able to use 3840x or 4096x for a monitor desktop setting supposedly the onboard displayport for that motherboard is capable of that.

The weird problem. Sound coming out of displayport from my Centos server is slow and low in pitch. (It also does the same thing with hdmi).
It looked like the official driver from AMD was from 2015 and breaks a lot of things. Other drivers when applied dumb the video down to 1024 x 768 and sound is completely disabled.

When playing a Madonna video "Power of Goodbye" it sound likes she's on ludes or in a thick alien atmosphere. Pitch is low and tempo is reduced.
When playing a 440 hz tone, the randomly chosen tuner app on my phone reported it to be between 331.5 and 331.6hz.

For grins I put in a spare Radeon 5450 temporarily. The sound seemed normal over HDMI (but no displayport on that card) so that complicates kvm.

I checked sampling rate files. I checked speeds. Started to mess around with the clock source but none of these things mattered.

CPU was running at 3800 and now it is turbo'd to 4300. Same slow audio response for the onboard audio over hdmi and displayport.

Is there something that can fix this?

(Otherwise I saw an open box Radeon card with 4k (or more) through displayport for under $100.)

Moschops
Posts: 2
Joined: 2018/12/20 17:29:49

Re: Radeon APU - HD 7660D - output to displayport off pitch / speed

Post by Moschops » 2019/01/16 22:39:16

Local computer store had an open box Radeon Pro WX2100 (Only $69). I installed that. It worked with native drivers.

Of course I had to break it/update it...

Used the following AMD driver for CentOS 7.6
https://www.amd.com/en/support/kb/relea ... 50-unified

Discovered at some point in the process the keyboard and mouse was deleted either by this driver or meddling with (deleting? oopsie) Xorg.
Booted to text mode by temporarily editing the kernel choices (before inputs failed).
Ran mouse, keyboard, and other file installs that had disappeared (off a webpage forum I can't currently find)

After some aggravation, brief consideration of going Redhat or Fedora, video and sound now work properly with the correct pitch and speed.

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