sobakakusaka, can you borrow a video card to test? If there is a problem with the IGU, then the card will not have these symptoms. I also think you need to contact AMD Online Support and see what they have to say. Thanks and enjoy, John.
sobakakusaka, please search for "AMD Online Support". If I post a link, especially on the weekend, there will be a delay. The video card looks good. Please give it a try and see if your problems go away and report it to AMD. Good luck and enjoy, John.
I certainly have an old asus engt240 video card, but I think that it is hardly suitable.
Also, how to contact online support?
That old card is not nearly powerful enough. You need a modern gaming card.