Issues with Radeon 5700 XT

Ryan Douglas

Staff member
We are seeing a pattern of users with the Radeon 5700 XT reporting problems.

Based on some preliminary research, it seems that many titles using DirectX 9 are affected, not just RealFlight.

We have ordered one of these cards so we can investigate further.

Obviously we can't try anything until ours arrives. If you feel like experimenting and have any success with forcing rendering to an on-chip GPU or by rolling back to earlier AMD drivers, please report back here.
Mine works again. Uninstalled Adrenalin and fresh install 20.4.2.

With all due respect I blame you for releasing a game in 2019 with DX9 and ONLY DX9 support when it is nearly 20 years old far more than I blame AMD for not supporting something rapidly approaching complete obsolescence.
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Ryan Douglas

Staff member
Thank you for coming back to report your findings. It gives us more data for when we investigate, and it will benefit other users as well. In fact, I will send a message to let the tech support team know.

While DirectX 9 is old, we are far from the only title still using it. On a bit of a side note, we have actually found that versions of DirectX far older than 9 are still supported in current Windows.

We're glad you are able to run RealFlight again!


New member
I have installed an RX 5700 XT with the latest GPU drivers (tried 20.7.2 and 20.8.2). On my system, RF9 goes not responding soon after loading the simulation environment. An earlier GPU driver did work, but this was unstable/unusable on my system, so I went back to the latest GPU driver. Not sure who can fix the issue, AMD or Knife Edge, but it would be great to get a fix so that I can use the software.


Well-known member
RX5700XT owners should adopt a two-prong approach to this matter. You should hammer on Radeon as well as Knife Edge. It seems that they have as much of an iron in the fire. If I bought that card, I would not be happy that it does not work with older software.
Our card arrived and we were able to test various drivers. Results with RealFlight mirror others':
  • With the "Recommended" (by AMD) 20.4.2 driver, RealFlight 9 runs fine.
  • With the "Latest" 20.8.1 driver, RealFlight 9 hangs on the loading screen and stops responding.
The "Recommended" driver is the one that AMD designates as stable. A quick survey suggests that the "Latest" driver, while not named as a beta, seems to have issues on many titles, not just RealFlight.

We'll convey this information to Product Support so that they can more quickly help other users.


New member
I too have done some research on the web and found that many of the people reporting trouble with dx9 on rx 5700 xt's are trying to run old software on new graphics. For Knife Edge to deliver brand new, latest, greatest software with old graphics is not commendable. If my findings are right, MS has not updated dx9 since 2010 which put the "new" RF9 in about the same category. Since then MS has updated to dx10, dx11, and dx12, what's happened with Knife Edge.
I need the latest Radeon drivers on my system to run the high performance graphics I need for sim racing so downgrading drivers is not an option. I've updated RF9 to 9.00.022
When I start RF9, I have win10's task manager showing on a second screen. Shortly after RF9 opens, the words "not responding" appear next to RealFlight 9 (32bit). The only way I can cancel RF9 is by using the end task button in task manager. Nothing on the RF9 screen works
Because RF9 is 32bit software, I tried to start RealFlight 9 Launcher in win10/64 "safe" mode. RF9 screen comes up and while "Initializing Height Map" bar appears, I get the following error message:
file: DXEffect.cpp
line: 850 & line: 910
Hopefully this info will help you find where the problem is in Knife Edge's RF9 software

Eddie Brown

New member
That is very interesting APEXer. I have just updated my 5700XT to 20.8.1. It still freezes as you describe. Just like you I do not want to revert to previous issues since I need the latest Radeon drivers to run high performance graphics. In any case I follow the policy of updating to the best at all times. Had I known that RF9 was based on such old systems I would not have purchased it.
There is nothing in the Horizon sales specs on what is required to run it that says that because of it`s aged origins it will not work with the latests technology.
And I certainly would not have purchased it had I realized how bad the support service is!
I bought it to prepare my grandson for his training at our flying club to pass his A Certificate. Can anybody recomend alternative simulator software that is good and actually works!

Ryan Douglas

Staff member
Finger-pointing isn't usually very productive, but for perspective I do think it's worth bearing in mind that yes, RealFlight 9 is based on an older version of DirectX, but we work correctly with that version of DirectX. As far as I know this problem is not happening because of a flaw in our implementation or some other bug that is unique to RealFlight; this problem is happening because AMD has broken something in a new driver that previously worked perfectly fine, and it is affecting not just RealFlight but many DirectX 9 applications. There is a one-to-many problem here, and it would be best addressed at the headwaters.

You are obviously free to have whatever policy you wish re: driver updates, but there is a reason AMD has such a thing as a "Recommended" driver and a separate "Latest" driver. As customers who are negatively impacted by changes they made in the latest version, I encourage you to let them know about how it has negatively impacted you and ask them to unbreak DX9 support in a new update--soon! Maybe they don't care (which would make me very angry as an AMD customer), or maybe it was completely accidental and they already have a fix in the works. Maybe they aren't in a rush because it's only a problem in the "Latest" driver. I can only guess. In any event, I imagine they are less likely to fix it if nobody seems bothered.

If there is something we can do on our end to work around this, we'll certainly do what we can. We have the specific card where the problem occurs now and can reproduce it, which is helpful. But it may be out of our hands, practically speaking. We can't just wave a wand and transform RealFlight 9 into a DX12 application. If it were that simple, it would have been done already. And again, compatibility has not been a problem except for this new and very narrow case.

Thank you again to everyone for reporting your results.


Well-known member
Why is it that the vast majority of Graphics cards are working fine with Real Flight 9? It seems that the finger-pointing should be at Radeon. FYI Knife Edge did release a software product for high-end computer equipment. It was a failure because most of their customers did not want to upgrade for better hardware. I am quite sure that KE is working on a future-looking product. In the meantime, they are keeping their bread and butter going. There are competing products, so go look at them or buy a compatible card.


Well-known member
I've been burned by using AMD/Radeon GPU's in the past with their awful drivers and support. I've stopped supporting AMD and refuse to use their products.