Are you looking for a high-end graphics card but are unsure which one to choose? What about an enthusiast class card? The AMD RX 6900 XT and the Nvidia RTX 3090 are at the top of the list, yet they differ in several crucial aspects, especially if it’s the “best of the best” you’re after.
Enthusiast-class GPUs offer unparalleled performance and image quality. My opinion is that Nvidia did everything better when comparing the 6900 XT vs 3090 (as it does very often in lower classes as well), and I’ll go into detail to explain why in this article.
6900 XT vs 3090 – Quick Comparison
Right off the bat, we can see that the RTX 3090 is a bit better on paper in almost every segment (see chart below) and outshines the 6900 XT in others. These differences may seem minuscule at first glance, but I’ll explain what they mean in the real world.
Both cards launched in the second half of 2020, the year of lockdowns and stay-at-home fun. These powerhouses offered more power, details, ray tracing, and 4K fun for anyone who could afford them at the time.
| Radeon RX 6900 XT | Specs | Nvidia RTX 3090 |
|---|---|---|
| Navi 21 XTX | GPU | Ampere GA102-300-A1 |
| PCIe 4.0 x16 (3-slot) | Interface | PCIe 4.0 x16 (3-slot) |
| Navi / RDNA2 (2020-2022) | Architecture | Ampere (2020-2022) |
| 5,120 Stream Processors | GPU Cores | 10,496 CUDA Cores |
| 320 | TMUs/Tensor Cores | 328 |
| 80 (Ray Tracing Accelerators) | RT Cores | 82 (Ray Tracing Cores) |
| 1,825 MHz | Base Clock | 1,395 MHz |
| 2,250 MHz | Boost Clock | 1,695 MHz |
| 3,000 MHz | Max Clock | 2,105 MHz |
| GDDR6 | Memory | GDDR6X |
| 16 GB | Memory Size | 24 GB |
| 2,000 MHz (16 Gbps) | Memory Speed | 1219 MHz (19.5 Gbps) |
| 512.0 GB/s | Bandwidth | 936.2 GB/s |
| 300 Watt | TDP (Founders Edition) | 350 Watt |
| 700 Watt | Required PSU (Founders Edition) | 750 Watt |
| 850 Watt | Recommended PSU (Founders Edition) | 850 Watt |
| 1x HDMI 2.1 2x DisplayPort 1.4a 1x USB Type-C | Outputs | 1x HDMI 2.1 3x DisplayPort 1.4a |
| Check Price on Amazon | Price | Check Price on Amazon |
RX 6900 XT
AMD started in 1969 in Silicon Valley and grew to become a global leader in GPU and CPU development. For years AMD struggled to keep up with Nvidia but is now back on track thanks to its recent models.
Back to the 6900 XT. A graphics card that sold out on the first day, AMD’s RX 6900 XT offered a significant boost in power required and performance offered in comparison to its predecessor. Like many other AMD cards, the 6900 XT is built to be overclocked and can handle almost anything that you throw at it.
Pros
- One of AMD’s fastest
- Large GDDR6 capacity
- Lower price
- Great for gaming
Cons
- No dedicated Ray Tracing Cores
- 3-slot
RTX 3090
Nvidia, founded less than 30 years ago, is the leader in GPU development. It has moved on to powering development in computing, robotics, self-driving vehicles, AI, and machine learning using its GPUs.
Like AMD’s 6900 XT, Nvidia’s GeForce RTX 3090 sold out almost immediately after its release in 2020 and is in scarce supply still. The 3090 reaches performance levels of Nvidia’s Titan class cards (thankfully, at a lower price).
Pros
- Exceptionally large VRAM
- Dedicated Ray Tracing Cores
- Great 4K gaming
- A bundle of built-in streaming features
Cons
- Price
- 3-slot
Key Specifications
Architecture
You can find AMD’s RDNA2 architecture in the Playstation 5 and XBOX Series S and X consoles and in the Radeon 6000 series of GPUs. RDNA 2 offers cool features not previously available to the masses, such as AMD Infinity Cache and Smart Access Memory.
Smart Access Memory enables enhanced access to GPU VRAM, allowing the whole of the VRAM to be accessed at once. Before this, VRAM could only use 256MB blocks. In 2020, Nvidia stated that it had the technology to rival AMD’s SAM in its architecture, but users would need to update and manually tweak their BIOS to achieve it.
Nvidia’s Ampere packs 28.3 billion transistors (26.8 billion in the 6900 XT), 82 dedicated Ray Tracing Cores, AI and deep learning hardware, and live streaming abilities that are among the best available. All in all, Ampere is considered one of the fastest GPU architectures in the world currently, but AMD’s SAM gives it a run for its money.
That said, I have to mention that Ampere is the leading engine powering the AI revolution and it is designed and used for much more than gaming. Its bandwidth reaches 936.2 GB/s (compared to the 6900 XT’s 512.0 GB/s) and handles higher resolutions better than the 6900 XT (on average).
Winner: GeForce RTX 3090
Clock Speeds & Overclocking
Have you tried overclocking your GPU? If you’re planning to, be careful. Overclocking can overheat your card to the extent of permanent failure if you’re not careful. Remember to maximize fan speed if you opt for manual overclocking. I recommend using AMD’s software for overclocking the 6900 XT and Nvidia’s software or MSI Afterburner for the RTX 3090.
The 6900 XT has clock speeds (both base and boost) above that of the 3090. Maybe this is why they can compete with each other at all. The AMD card’s base speed is 1,825 MHz, while its boost designation is set at 2,250 MHz. The maximum clock speed it can hit is 3 GHz. When compared to the 6900 XT, Nvidia’s 3090 seems to fall short.
The 3090 has a base clock speed of only 1,395 MHz and a boost speed of 1,695 MHz, less than the base speed of the 6900 XT. Its max speed is in between the base and boost speeds of the 6900 XT, resting at 2,105 MHz.
| RX 6900 XT | Boost Clock | RTX 3090 | Boost Clock |
|---|---|---|---|
| ASUS ROG STRIX LC RX 6900 XT GAMING TOP | 2,525 MHz | EVGA RTX 3090 KINGPIN | 1,920 MHz |
| GIGABYTE AORUS RX 6900 XT Xtreme WaterForce WB | 2,525 MHz | EVGA RTX 3090 KINGPIN Hydro Copper | 1,920 MHz |
| Sapphire TOXIC RX 6900 XT Extreme Edition | 2,525 MHz | ASUS ROG STRIX RTX 3090 GAMING OC | 1,860 MHz |
| XFX Speedster ZERO RX 6900 XT WB | 2,525 MHz | ASUS ROG STRIX RTX 3090 GUNDAM OC | 1,860 MHz |
| XFX Speedster MERC319 RX 6900 XT Limited | 2,495 MHz | ASUS ROG STRIX RTX 3090 OC EVA Edition | 1,860 MHz |
Winner: Radeon RX 6900 XT
Cores
AMD’s Stream Processors vs Nvidia’s CUDA Cores — their names differ, but they do the same thing essentially, and the more of them you have, the better your experience will be. Similar to your multiprocessor CPUs (parallel processors), GPUs have multiple cores as well, only they number in the thousands. In this case, 5,120 vs 10,496 to be exact (in favor of the 3090).
With almost double the cores that the 6900 XT has, the RTX 3090 can handle a lot of calculations enabling you to run whatever you want on your PC with ease. These cores process numerous calculations as required by the GPU and handle aspects such as lighting and shadows, physics, anti-aliasing, and in-game ambient occlusion. Quite a lot.
Winner: GeForce RTX 3090
VRAM and Memory Specs
Nvidia used GDDR6X VRAM in the RTX 3090, a type of G6 memory that is faster than regular GDDR6. Add to that the fact that the 3090 has 24 GB of VRAM (compared to the 16 GB of the 6900 XT), there is no doubt that it is the better card. The 6900 XT has 16 GB, which is still a lot of VRAM.
Both are a pretty good investment in this right, as both 16 and 24 GB will keep you gaming for a long time to come. Nevertheless, the 6900 XT’s test results (we’ll get into that later) are more comparable to Nvidia’s RTX 3080 than the RTX 3090.
Winner: GeForce RTX 3090
Shaders, RT cores, and TMUs
AMD’s 6900 XT has slightly lower performance than Nvidia does with the 3090. This is attributed (in part) to the fact that Nvidia separated ray tracing from other computations. While AMD has Ray Tracing Accelerators as part of the Compute Unit structure in RDNA 2, Nvidia is on its second generation of Ray Tracing Cores.
Ray tracing is the digital world’s version of light and how light particles act in virtual spaces. It simulates the real thing as best it can (and looks better every year). Nvidia’s dedicated RT Cores are significant because they handle only ray tracing, while AMD’s compute units have to balance between ray tracing and other computations.
Shaders, which are generic programs that calculate optimal light, darkness, and color settings, work together with the RT cores in the 3090 when rendering 3D images on your screen. Shaders are directly handled by the primary GPU cores (Stream and CUDA), meaning that the number comparison that was in favor of the 3090 earlier applies here as well.
| RX 6900 XT | Shaders | RTX 3090 |
|---|---|---|
| 12 Ultimate (12_2) | DirectX | 12 Ultimate (12_2) |
| 4.6 | OpenGL | 4.6 |
| 2.1 | OpenCL | 3.0 |
| 1.3 | Vulkan | 1.3 |
| 6.7 | Shader Model | 6.6 |
Texture Mapping Units, or TMUs (Tensor cores), handle textures (did you see that coming?) and are critical in video game rendering. Without them, textures of in-game objects would slip away whenever you moved or changed your angle of view. Both cards have a similar number of Tensor cores, but the RTX 3090 has slightly more than the 6900 XT (328 vs 320).
Winner: GeForce RTX 3090
Performance & Resolution Tests
When you max both cards out, most performance test results are in favor of the 3090, which consistently offers more fps at lower loads, and a better visual experience. Even the RTX 3080 Founders Edition hits better results than the 6900 XT (on average). Advertised benchmark test favor the 6900 XT, but I’ve learned not to believe AMD’s marketing department.
Advertised benchmark tests show a 10% advantage for the 6900 XT at 1080p.
The 6900 XT continues to dominate in advertised benchmark test, dropping its lead to under 10%.
At 4K, the difference drops to 5% for the 6900 XT.
Real-world results paint a completely different picture. According to 146,035 users, the RTX 3090 offers 27% better EFps during gaming (effective speed), a 21% average score advantage in, and 23% better results when both cards are overclocked.
There are some games in which the 6900 XT trumps the 3090, but they are rare. The results are in favor of the 3090, even more when you turn ray tracing on at 4K (feeling those RT Cores now, Nvidia) and DLSS. The 6900 XT just can’t handle those loads with the ease that the RTX 3090 does.
I found Cyberpunk 2077 to be one of the better examples where the RTX 3090 offered almost double the fps of the 6900 XT on all resolutions.
Winner: GeForce RTX 3090
Connectivity
The 6900 XT has one HDMI port, two DisplayPorts, and one USB-C port. The RTX 3090 has one HDMI port and three DisplayPorts, but no USB-C port. The RTX 3090 FE has a 12-pin connector, while third-party cards have 2 x 6-pin or 2 x 8-pin connectors. The 6900 XT has two standard 8-pin connectors.
Winner: Draw
TDP
TDP (typically) refers to Thermal Design Power, a measurement of the maximum power a subsystem is allowed to draw from the PSU of your PC. It also refers to the maximum heat a component can handle.
When considering the Founders Editions of both cards, the 6900 XT uses 300 Watts of power, while the 3090 uses 350 Watts. The 6900 XT maxes out at 160°F (71.1°C) at artificial loads and averages 140°F (60°C) during gaming. The RTX 3090 maxes out at 185°F (85°C) and averages at 148°F (64.6°C).
Note that these figures (both power and temperatures) vary in third-party manufacturers’ versions, depending on build, clocking, fans, and other aspects.
Winner: Radeon RX 6900 XT
Also Read: [Complete Guide] How to Undervolt your CPU and GPU [SAFE]
Design and Build
Nowhere is this segment more relevant than when we compare the 6900 XT vs the 3090 due to their size. Both are 3-slot cards, so get ready to adjust your build (or make a new build) to accommodate the sheer size of these things. The RTX 3090 FE (Founders Edition) is very long, reaching 313 mm (12.3 inches).
The 6900 XT is slightly shorter, measuring 267 mm (10.5 inches) in length, but with 50 mm (2 inches) in height, it will eat up quite some space within your PC case. The Founders Edition 6900 XT has no vents on its back side through which it can vent hot air out of your case. Instead, hot air from its three fans circulates throughout your case.
The RTX 3090 FE was produced with a diagonally protruding pin connector for the 12-pin PSU connector, a good idea considering the card’s size. Third-party cards use other connectors.
Winner: GeForce RTX 3090
Also Read: GPU Fans Not Spinning: Common causes and how to fix!
RX 6900 XT vs RTX 3090 – Standout features
Nvidia’s Ray Tracing Cores make all the difference. Segmenting calculations to specific cores allows the RTX 3000 series to offer us almost unparalleled gaming.
Pricing & Availability
When released, the 6900 XT FE had an MSRP of $999, while the RTX 3090 was priced at $1499. Quite a difference. Due to their unavailability, these prices have risen. Thankfully, today the market is flooded with third-party versions of both cards.
You can find overclocked versions of the 6900 XT from MSI, GIGABYTE, ASUS, and others. The same goes for the 3090, with overclocked versions by MSI, GIGABYTE, ASUS, and many others available on the market.
Conclusion
If I just tally up the winners vs losers of each segment in this article, things are definitely in favor of Nvidia’s 3090. That said, there is a price difference that goes into play when choosing between the 6900 XT vs RTX 3090, in favor of the 6900 XT. There is also a performance, VRAM, and core count difference, all in favor of the 3090.
If you have the means, purchase the RTX 3090. You’ll future-proof your PC for years to come. But if you don’t feel that the 3090’s prices are something you can handle, the 6900 XT will keep you satisfied for years as well.
