Introduction

We have with us the ASRock Radeon RX 6900 XT OC Formula, the company’s new flagship graphics card, positioned a notch above even the RX 6900 XT Phantom Gaming. This sees the company revive its topmost “OC Formula” brand co-developed by Nick Shih, which represents the company’s boutique range of motherboards and graphics cards for professional overclockers taking a crack at world records of all shapes and sizes. What triggered the company to come out with an RX 6900 XT-based graphics card in particular, is a concerted preemption by AMD to NVIDIA’s rumored GeForce RTX 3080 Ti, an SKU slotted between the RTX 3080 and RTX 3090.

The Radeon RX 6900 XT GPU at the heart of the ASRock RX 6900 XT OC Formula isn’t the same chip as the one in the RX 6900 XT Phantom Gaming. AMD refers to this silicon as the Navi 21 “XTXH”. It is the highest bin of the Navi 21, designed to sustain up to 10% higher clock speeds than the regular RX 6900 XT. With its default “performance” BIOS, the RX 6900 XT OC Formula can now boost up to 2475 MHz, and achieve game clocks of up to 2295 MHz. The reference AMD Radeon RX 6900 XT sustains only up to 2250 MHz boost, and 2015 MHz game clocks, while ASRock’s previous RX 6900 XT-based flagship, the RX 6900 XT Phantom Gaming, does 2340 MHz boost, with 2105 MHz game clocks. Compared to the reference design, that’s exactly a 10 percent OC from ASRock.

The AMD Radeon RX 6900 XT is AMD’s current-generation flagship graphics card, which, along with the RX 6800 series, propelled the company back to the big leagues of enthusiast-segment graphics cards against NVIDIA. The RX 6900 XT is powered by AMD’s RDNA2 graphics architecture, which is its first to feature full DirectX 12 Ultimate readiness, including real-time raytracing. The RDNA2 architecture transcends platforms, and also powers the latest PlayStation 5 and Xbox Series X/S consoles, which makes it easier for game developers to optimize for the architecture on the PC.

At the heart of the RX 6900 XT is the 7 nm Navi 21 silicon, which it maxes out. This chip features 5,120 stream processors spread across 80 RDNA2 compute units, 80 Ray Accelerators (components that accelerate raytracing), 288 TMUs, 128 ROPs, and an impressive 16 GB of GDDR6 memory. This memory, however, runs across a 256-bit wide memory interface. AMD attempted to shore up bandwidth by using the fastest JEDEC-standard 16 Gbps memory chips, and deploying Infinity Cache, a 128 MB last-level cache on the GPU die, which speeds up transfers between the GPU and the memory, by acting as a scratchpad. Together with the GDDR6 memory, Infinity Fabric unleashes memory bandwidths of up to 2 TB/s.

The ASRock RX 6900 XT features the company’s most opulent custom board design to date, with a large triple-slot, triple fan cooling solution that’s packed with innovations; the company’s most over-the-top power-delivery solution ever on a graphics card; and design optimization for professional overclocking using liquid- or extreme cooling methods. The Navi XTXH silicon not only sustains boost frequencies better, but is also designed for better overclocking headroom than the original Navi 21 XTX powering the reference RX 6900 XT. In this review, we take our first look at this exotic new graphics card to tell you if ASRock has tangibly improved performance of the RX 6900 XT over the reference, and whether it gets any closer to the RTX 3090.