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The Radeon RX 6900/6950 XT Owners Thread.

Having just got a 6900xt and not built in a while. How do people undervolt these days? Is there and software, alt software or via bios?
Is there an easy to use benchmark software to evaluate performance against while undervolting etc? Many thanks.
Undervolt using AMD Software. Generally speaking, run stock core clock and undervolt in 0.025mv increments until you encounter instability. Starting voltage for XTX will be 1175mv and 1200mv for XTXH so you can work down from there. Set power limit to +15%. Memory can be set to 2112Mhz fast timings enabled. Click Apply to save settings and enjoy! For more information refer to an article i wrote here.
 
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Undervolt using AMD Software. Generally speaking, run stock core clock and undervolt in 0.025mv increments until you encounter instability. Starting voltage for XTX will be 1175mv and 1200mv for XTXH so you can work down from there. Set power limit to +15%. Memory can be set to 2112Mhz fast timings enabled. Click Apply to save settings and enjoy! For more information refer to an article i wrote here.
Perfect, many thanks.
 
Having just got a 6900xt and not built in a while. How do people undervolt these days? Is there and software, alt software or via bios?
Is there an easy to use benchmark software to evaluate performance against while undervolting etc? Many thanks.

Yeah AMD software as said, my undervolt has been stable since i did about a month ago. Played COD MW2, BF2042 and no crashes.
 
The only other thing I've done since installation a month or so ago is adjust the fan curve to be slightly more aggressive (so they run most of the time at between 40-50% at 60-70c)) but still not intrusive whilst playing games or under load. Primarily to keep the hot spot temp <95 (I've a Fractal Define 7 with limited airflow), as I found the default curve was getting to 100 hotspot with extended sessions on full load. It now goes between low 80s to low 90s, but doesn't runaway like it did.

So that and the slight undervolt is all I feel I've needed to do. I've not messed with the clocks (default is 2524) or power slider.

For reference the card is an Asrock Rx6900XT Phantom and refresh rate of my 2K monitor is usually set to 120mhz. All settings applied in the AMD drivers.

Edit to add - Although I don't usually spend as much on the GPU as I did on this one (i'm very much in the £300-£400 spending bracket (or lower!) usually), this card is working out brilliantly, especially with the expected prices of the models intended to replace it and their expected (lack of) performance gains at the pricepoint I paid and had games thrown in.
 
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I have the toxic 6950xt water cooled card, and the fan on the GPU board is self is stupidly loud above like 2550mhz, is there anyway to control this fan?
 
I have the toxic 6950xt water cooled card, and the fan on the GPU board is self is stupidly loud above like 2550mhz, is there anyway to control this fan?
You should be able to control it with the AMD tuning part of the driver software. You will need to setup a custom fan curve.
 
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So ive got the Red Devil 6900xt installed at last. A small undervolt to 1110 from 1200 standard mV (prob could go further) vram fast timmings to 2110 and power limit +15%. feels like the card could do more and certainly can get the clock towards 2600mhz without too much trouble but prefer to keep temps down. 5600x running super cool in fractal meshify and peerless assassin, and GPU under stress test gets to around 65C with hotspot at 80 to 85C, hotspot was hitting 90+C when clock was towards 2600mhz but have limited clock to about 2500mhz with the undervolt. Dont know how to post pictures so link below to screenshoot.

Does this all look pretty standard/ good to people? cheers.

 
So ive got the Red Devil 6900xt installed at last. A small undervolt to 1110 from 1200 standard mV (prob could go further) vram fast timmings to 2110 and power limit +15%. feels like the card could do more and certainly can get the clock towards 2600mhz without too much trouble but prefer to keep temps down. 5600x running super cool in fractal meshify and peerless assassin, and GPU under stress test gets to around 65C with hotspot at 80 to 85C, hotspot was hitting 90+C when clock was towards 2600mhz but have limited clock to about 2500mhz with the undervolt. Dont know how to post pictures so link below to screenshoot.

Does this all look pretty standard/ good to people? cheers.

Give 2499min 2599max a try. check to voltage in HWinfo64 as if you go too far the undervolt goes out of the window and the card pulls what it needs to not crash.
What is your default max on the slider when opening the drive by the way?
 
Give 2499min 2599max a try. check to voltage in HWinfo64 as if you go too far the undervolt goes out of the window and the card pulls what it needs to not crash.
What is your default max on the slider when opening the drive by the way?
Thanks. Out at mo so will try later. Default on which slider, the voltage? Was set at 1200mv out the box. Not sure on clock speeds, guess if unselect custom GPU clocking it will reset those to check?
 
Thanks. Out at mo so will try later. Default on which slider, the voltage? Was set at 1200mv out the box. Not sure on clock speeds, guess if unselect custom GPU clocking it will reset those to check?
Ye, the max (MHz) slider clock when reset and opened up. Helps to give you an idea of where you'll get and quality of the silicone.
 
Ye, the max (MHz) slider clock when reset and opened up. Helps to give you an idea of where you'll get and quality of the silicone.

its says it goes upto 4000mhz..? when i click back to deafult and then back to custom and slide the max freq slider. Does this mean i should be able to push it a bit harder? but would need overvolting etc probably? 4000 seems a bit ridiculous? more concerned card runs nice and cool vs maxed out.
 
That does crash the system thou when I apply it!

btw what junction temp should we be aiming for in stresstest? mine is around 84C, and theres a 18C diff between normal card temp (64C) and hotspot (83C)? am i being over precious with keeping temps down so I could let that go higher and clock higher?
 
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its says it goes upto 4000mhz..? when i click back to deafult and then back to custom and slide the max freq slider. Does this mean i should be able to push it a bit harder? but would need overvolting etc probably? 4000 seems a bit ridiculous? more concerned card runs nice and cool vs maxed out.
I ment reset and then just open the tab. So the default driver set value in the max slider. Mine is 2504MHz for example.
 
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