6900 XT vs 7900 XT

[HeyItsChris]

Can someone explain in detail how much faster a 7900 XT is than the 6900 XT on Topaz Video Ai software?

 

Currently going from 1080p to 4K, I get like if I get lucky 2 fps on my Vega 56 with Vega 64 BIOS, thoroughly optimized for this task because it's insanely demanding.

 

It hits the 3D engine hard, not the compute.  So what kind of fps would I get with a 6900 XT vs 7900 XT?

 

If my math is correct, with my Vega 56 3584 shader units, I get 2 fps, then a 6900 XT would be 5120 which is 42.86% more so that could yield 2.8572 fps but I guess with architectural & clock improvements it should yield 3-4 fps?

 

Then we get to the 7900 XT @ 5376 shader units which may yield 3 fps, but with architectural improvements from RDNA 2 to RDNA 3, could see possibly 5-6 fps?  

 

Or am I nuts & I'm looking at my original calculations?

Thanks

 

 

[SoloCamo]

Not a big difference between the two considering the 7900XTX was barely faster... if you already have the 6900XT I wouldn't bother with the upgrade to a 7900XT and that includes for every task outside of Topaz as well.   That said if you are considering both of these over your current Vega 56, I'd go with the one you can get at a better cost/performance.   7900XT does have other benefits though such as AV1 encoding and newer features plus the extra 4gb of vram.

 

 

Edited June 2 by SoloCamo

[HeyItsChris]

Thanks for the chart bro!  That makes it so clear to me.  Yeah I can get the 6900 xt for 449 or the 7900 xt for 799, i guess its quite clear 6900 xt is better for the price.

[SoloCamo]

13 hours ago, HeyItsChris said:

Thanks for the chart bro!  That makes it so clear to me.  Yeah I can get the 6900 xt for 449 or the 7900 xt for 799, i guess its quite clear 6900 xt is better for the price.

 

All good.  6900XT's are getting hard to find so do consider the 6950XT's as well, they will close the gap even further on the 7900XT.

[HeyItsChris]

Whats the shader core difference between 6900xt and 6950xt?  I thought that were essentially the same card.

[SoloCamo]

15 minutes ago, HeyItsChris said:

Whats the shader core difference between 6900xt and 6950xt?  I thought that were essentially the same card.

 

No difference aside from higher clock speeds for the core and different memory which gives a nice bandwidt bump.  I'd imagine that would help with this type of work but I'm talking minuscule numbers here.  I only bring it up because 6950xt's are usually around the same price.

[Sir Beregond]

Yep exactly. 

 

AMD Radeon RX 6900 XT Specs | TechPowerUp GPU Database

WWW.TECHPOWERUP.COM

---

AMD Navi 21, 2250 MHz, 5120 Cores, 320 TMUs, 128 ROPs, 16384 MB GDDR6, 2000 MHz, 256 bit

AMD Radeon RX 6950 XT Specs | TechPowerUp GPU Database

WWW.TECHPOWERUP.COM

---

AMD Navi 21, 2310 MHz, 5120 Cores, 320 TMUs, 128 ROPs, 16384 MB GDDR6, 2250 MHz, 256 bit

 

Same shader count, but you can see the boost to the base, game, boost clocks, as well as the memory clock on the 6950 XT to 18Gbps up from 16Gbps on the 6900 XT.

Edited June 4 by Sir Beregond

[HeyItsChris]

So, thats gonna help a lot with more memory bandwidth, from 16 to 18 giga bits per second, that's a big jump not obtainable from overclocking the memory on the 6900 xt?

 

I see the 6900 xt red devil ultimate for 449 & they didn't make a red devil 6950 xt, i don't think?  I prefer the red devil as its the heaviest coolest running heatsink with the lowest load temps on the core & hotspot.

 

Can someone find proof of the exact hotspot temp on the 6900 xt red devil & compare it to the 6950 xt & the memory temps?

 

Thanks

 

Nevermind I found the red devil 6950 xt for 499 vs the 6900 xt for 449.... might as well pay 50 bucks for the faster ram and faster stock clocks...

Edited June 4 by HeyItsChris

[SoloCamo]

19 hours ago, HeyItsChris said:

So, thats gonna help a lot with more memory bandwidth, from 16 to 18 giga bits per second, that's a big jump not obtainable from overclocking the memory on the 6900 xt?

 

Max overclock on the 6900XT (non liquid cooled versions as the LC versions had 18gbps) is 550GB/s  stock being 512GB/s.  However, most people usually only get it stable around 537GB/s.  The 6950XT can be pushed over 600GB/s which helps a lot in some instances, especially higher resolution gaming. 

 

That said, another card you may want to consider is the 7900GRE if it's in your price range.  16gb also with comparable performance, less power use and newer features. 

[HeyItsChris]

I'm really looking for 128 ROPs at the bare minimum though on my next upgrade from my late 6600 XT & Vega 56 on Vega 64 BIOS.

 

Do you honestly think I can power a 6800 xt or 6900 xt or 6950 xt with this psu?  It powers my Vega at 250W without breaking a sweat, and can also handle as much as 350W TDP 350A TDC, although the cooler can only handle 250W max on my Powercolor Red Dragon Vega 56 cooler with fresh hi-perf pads & paste.  Temps are solid at 250W.  Its that I bought this case, the Silverstone Milo 12 to stuff everything into & I see the 6800 XT+ is expecting 950W recommended.  I have a very reliable 1000W Kingwin, but space is limited in the case.  

 

Your thoughts?

 

AMD Ryzen 7 3700X AMD Radeon RX 6950 XT - PSU Calculator - Build XAWn9p

OUTERVISION.COM

---

AMD Ryzen 7 3700X AMD Radeon RX 6950 XT - Power Supply Calculator Build XAWn9p

 

EVGA 650 BP, 80+ BRONZE 650W, 3 Year Warranty, Compact 120mm Size, Power Supply 100-BP-0650-K1

WWW.EVGA.COM

---

Precision is power, as the EVGA BP power supplies add another affordable option to EVGA's 80PLUS Bronze-certified lineup, while reducing the overall length to 120mm - EVGA's shortest ATX power...

 

Edited June 15 by HeyItsChris

[Fluxmaven]

Many people tend to go way overboard on PSUs. I have a reference 6950 XT under a custom waterblock that I run on an AX760. I haven't had any issues with it. It's paired with a 7800X3D. I also briefly ran it on an SF600 with a 7900X and had a couple shutdowns until I put CPU in eco and did a mild undervolt and capped FPS on the GPU. 

 

The reason people recommend 1000w PSU for these cards is the transient power spikes. Higher quality PSUs do a better job of handling spikes without tripping OCP. The 650 BP will be a little iffy but you can try it and if you have issues try and shoehorn your 1000w into that system. 

[The Pook]

24 minutes ago, Fluxmaven said:

The reason people recommend 1000w PSU for these cards is the transient power spikes. Higher quality PSUs do a better job of handling spikes without tripping OCP. The 650 BP will be a little iffy but you can try it and if you have issues try and shoehorn your 1000w into that system. 

 

I still feel salty about retiring my 750W because my 3080 Ti's transient spikes. Total power consumption was never an issue

[SoloCamo]

2 hours ago, Fluxmaven said:

Many people tend to go way overboard on PSUs. I have a reference 6950 XT under a custom waterblock that I run on an AX760. I haven't had any issues with it. It's paired with a 7800X3D. I also briefly ran it on an SF600 with a 7900X and had a couple shutdowns until I put CPU in eco and did a mild undervolt and capped FPS on the GPU. 

 

The reason people recommend 1000w PSU for these cards is the transient power spikes. Higher quality PSUs do a better job of handling spikes without tripping OCP. The 650 BP will be a little iffy but you can try it and if you have issues try and shoehorn your 1000w into that system. 

 

This...

 

Though I must admit my EVGA SuperNOVA 750 P2 has done an absolutely excellent job handling a 11900k and 6900XT...  No issues whatsoever and I know the spikes are a real problem for this generation of cards from both Nvidia and AMD. 

 

  

12 hours ago, HeyItsChris said:

Do you honestly think I can power a 6800 xt or 6900 xt or 6950 xt with this psu?

 

 

Keep in mind, the 6900XT is actually more efficient than the 6800XT and power use between the two is near identical. 

Edited June 15 by SoloCamo

[HeyItsChris]

Oh, wow thanks for all the important information i needed!  Thank you so much.

[HeyItsChris]

I cannot wait to buy a 6950XT that's gonna be so flippin wicked broskis!

 

I wish you guys had some good gameplay videos of your 6900XT or 6950XT in action.

 

Don't bother if you can't keep the Hotspot below 84C.  I only want to see the people who monitor their hotspot & keep it in check, below 84C.  When I see above 90C, that hurts my heart because that poor masterpiece of a GPU is getting hurt.  The silicon will fail above 90C, particularly above 84C, damage occurs.  That's why so many people have only received a matter of short few years or months of use even.  

 

I wanna see peoples videos of them fine-tuning their MorePowerTool with 84C temp limits & 88C shutdown & fans kick in to full speed at 40C, to keep the dreaded Hotspot in check.

 

Cya guys

[J7SC_Orion]

The 6900XT is on one of my machines - got it back in the spring of 2021, mostly for productivity as my gamer system runs a w-cooled 4090. Still, the 6900XT is also w-cooled (Bykski block) and with that I can let MorePowerTool/ MPT do its thing per sample below (Geekbench GPU run). MPT is great for a 6900 XT or 6950 XT as it allows them to get close to a 7900  XT - and MPT does not work with the Radeon 7K series anymore. As long as you can properly cool the 6900/6950, it has a lot of headroom. Its only real drawback is its 4K performance...but at 1440, it is a charm and still one of the best deals out there, IMO.

 

[pio]

7 hours ago, J7SC_Orion said:

The 6900XT is on one of my machines - got it back in the spring of 2021, mostly for productivity as my gamer system runs a w-cooled 4090. Still, the 6900XT is also w-cooled (Bykski block) and with that I can let MorePowerTool/ MPT do its thing per sample below (Geekbench GPU run). MPT is great for a 6900 XT or 6950 XT as it allows them to get close to a 7900  XT - and MPT does not work with the Radeon 7K series anymore. As long as you can properly cool the 6900/6950, it has a lot of headroom. Its only real drawback is its 4K performance...but at 1440, it is a charm and still one of the best deals out there, IMO.

 

My experience was quite the opposite with my 6900XT.  Mine is an MSI design, which uses direct touch heatpipe cooling.  As such, there's too many gaps I think on the die, which results in waaay higher hotspot temps.  That's my theory, because cards that seem to have a solid coldplate APPEAR to do better with hotspot temperatures.  My card has been repasted with PTM7950, and used putty in place of the pads.  It helped, but my hotspot is STILL hitting 95*C and there's nothing I can do short of lowering the power limit on the card to like -15% or something.  Core hardly ever even breaks 50*C.

So if you're stuck to using the stock cooler, look for teardown reviews and make sure its got a solid coldplate first on the cooler.  If you're planning on aftermarket cooling it, by all means they should all be pretty fair game I'd imagine then (depending on the cooling method / block of choice).  They really are GREAT cards, I run mine 1440p for game recording all the time.

Edited June 19 by pio

[HeyItsChris]

Thanks guys Im gonna buy the Powercolor Red Devil RX 6950 XT hopefully.  Its a copper plate that the silicon touches from what I've seen from teardowns.  Its the heaviest of all heatsinks & runs the coolest amongst all the others.  Hopefully i can find one at a good price.