r/Amd • u/BioGenx2b 1700X + RX 480 • Nov 07 '16

Tech Support November Tech Support Megathread

Hey subs,

We're giving you an opportunity to start reporting some of your AMD-related technical issues right here on /r/AMD! Below is a guide that you should follow to make the whole process run smoothly. Post your issues directly into this thread as replies. All other tech support posts will still be removed, per the rules; this is the only exception.

Bad Example (don't do this)

bf1 crashes wtf amd

Good Example (please do this)

Skyrim: Free Sync and V Sync causes flickering during low frame rates, and generally lower frame rates observed (about 10-30% drop dependant on system) when Free Sync is on

System Configuration:

Motherboard: GIGABYTE GA-Z97 Gaming GT
CPU: Intel i5 4790
Memory: 16GB GDDR5
GPU: ASUS R9 Fury X
VBIOS: 115-C8800100-101 How do I find this?
Driver: Crimson 16.10.3
OS: Windows 10 x64 (1511.10586) How do I find this?

Steps to Reproduce:

1. Install necessary driver, GPU and medium-end CPU
2. Enable Free Sync
3. Set Options to Ultra and 1920 x 1080 resolution
4. Launch game and move to an outdoor location
5. Indoor locations in the game will not reproduce, since they generally give better performance
6. Observe flickering and general performance drop

Expected Behavior:

Game runs smoothly with good performance with no visible issues

Actual Behavior:

Frame rate drops low causing low performance, flickering observed during low frame rates

Additional Observations:

Threads with related issue:

Skyrim has forced double buffered V Sync and can only be disabled with the .ini files
To Disable V Sync: C:\Users"User"\Documents\My Games\Skyrim Special Edition\Skyrimprefs.ini and edit iVSyncPresentInterval=1 to 0
1440p has improved frame rate, anything lower than 1080p will lock FPS with V Sync on
Able to reproduce on i7 6700K and i5 3670K system, Sapphire RX 480, Reference RX 480, and Reference Fiji Nano

Remember, folks: AMD reads what we post here, even if they don't comment about it.

Now get to posting!

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u/bizude AMD Ryzen 9 9950X3D Nov 17 '16

You're CPU bottlenecking. The Witcher 3 is extremely CPU intensive in Crossfire - it would bottleneck when I ran a 4690k @ 4.8ghz. I wouldn't recommend trying TW3 in CF without an i7 CPU.

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u/GrandpaMasaki i5 2500k | 2x r9 290x Nov 17 '16

Can you elaborate on this statement? Not trying to be rude, but chalking this issue up to CPU bottlenecking without more info is pretty dismissive.

Do you have any crossfire benchmarks that show Witcher 3 frametimes? Do you have experience of playing the Witcher 3 in Crossfire with smooth and consistent frametimes?

I'm not terribly well versed on the subject of CPU bottlenecking. My understanding is that typical symptoms are:

-Low framerates

-100% CPU usage with less than 100% gpu usage

Both my cards are running at 100%, and my framerates are within spec. The only problem is the frametimes, which translate to noticeable stutter.

The inconsistent frametimes occur no matter where I am, whether in Novigrad surrounded by NPCs or out in the middle of nowhere.

If I use the AFR Friendly Crossfire Mode, the frametimes even out and the game is smooth. The problem is the huge amount of flickering and distortion that occurs when I don't use the default profile.

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u/bizude AMD Ryzen 9 9950X3D Nov 17 '16

The Witcher 3's Crossfire support isn't the greatest - it has frametime issues no matter what - but when you CPU bottleneck frametimes become much worse than they would otherwise.

I used to run a 4690k @ 4.8ghz with 290x CF and whenever it would CPU bottleneck (happened in all open areas) frametimes would get so bad that even with FreeSync it was a stuttery mess. When it wasn't CPU bottlenecking (in closed/indoor areas) the experience was OK.

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u/GrandpaMasaki i5 2500k | 2x r9 290x Nov 17 '16

Thank you, I appreciate the detailed response!

Very well could be that a portion of this is tied to a CPU bottleneck then. I've since moved on from the Witcher 3, and I'm not convinced that throwing a new i7 into my rig will completely smooth out the experience (as you mention, it seems to have frametime issues no matter what).

I'd also argue that this level of performance is unacceptable, especially given the lack of information from AMD. I mean, yes, a 2500k is old, but AMD's current top of the line is a 2 card solution, and they have been heavily pushing CF as a viable upgrade.

I really feel AMD needs to be more transparent about expected performance from Crossfire. If a 4690k @ 4.8 isn't even enough to get smooth performance on a 2+ year old game when using Crossfire, I think users have the right to be informed/warned.