Speculation around the graphics card world is that the Radeon RX 6900 XT LC could very well be the incarnation of the rumored Radeon RX 6900 XTX. The latter was expected utilize the Navi 21 XTXH silicon, which allegedly brings the highest clock rates out of AMD's RDNA 2 army. Although we've already seen the graphics card in the wild, AMD hasn't formally confirmed the existence of the Radeon RX 6900 XT LC.
The Sapphire Radeon RX 6900 XT LC, which should employ the Navi 21 XTXH die, comes with 80 Compute Units (CUs) for a total of 5,120 Stream Processors (SPs). Along with those 5,120 SPs, you'll also find 80 ray accelerators for ray tracing workloads. The Radeon RX 6900 XT LC arrives with a 2,250 MHz game clock and a boost clock up to 2,435 MHz. The vanilla Radeon RX 6900 XT has a 2,015 MHz game clock and 2,250 MHz boost clock. Therefore, Sapphire's rendition is offering up to 11.7% and 8.2% higher game and boost clocks, respectively.
Besides the uplift in clock speeds, Kabum's specification table also shows an increase in memory speed for the Radeon RX 6900 XT LC. Apparently, the liquid-cooled version sports 18 Gbps GDDR6 memory chips as opposed to the 16 Gbps ones on the Radeon RX 6900 XT. It may be a human error, but it's certainly feasible, considering that Samsung produces 18 Gbps GDDR6 memory chips. If accurate, the extra frequency on the memory chips bumps the Radeon RX 6900 XT LC's maximum theoretical memory bandwidth up to 576 GBps, a 12.5% improvement over the regular version.
AMD Radeon RX 6900 XT LC Specifications
|Radeon RX 6900 XT LC*||Radeon RX 6900 XT|
|Architecture (GPU)||RDNA 2 (Navi 21)||RDNA 2 (Navi 21)|
|CUDA Cores / SP||5,120||5,120|
|Base Clock Rate||?||1,825 MHz|
|Game Clock Rates||2,250 MHz||2,015 MHz|
|Boost Clock Rate||2,435 MHz||2,250 MHz|
|Memory Capacity||16GB GDDR6||16GB GDDR6|
|Memory Speed||18 Gbps||16 Gbps|
|Memory Bandwidth||576 Gbps||512 GBps|
|Transistor Count||26.8 billion||26.8 billion|
|Die Size||536 mm²||536 mm²|
*Specifications are unconfirmed.
The Sapphire-branded Radeon RX 6900 XT LC (21308-02-10G) shares the same design as the Radeon RX 6900 XT LC that recently popped up inside a gaming PC over in China. Although listed as a Sapphire SKU, there are no signs of the Sapphire logo or any type of third-party marketing on the graphics card itself.
It stands to reason that the Radeon RX 6900 XT LC likely conforms to an AMD reference design where the chipmaker's partners are free to slap their name beside the Big Navi graphics card. It flaunts a dual-slot design with aluminium plates on both sides of the graphics card. For comparison, the Radeon RX 6900 XT reference edition conforms to a 2.5-slot design. Evidently, there are no cooling fans so the Radeon RX 6900 XT LC's only method of staying cool is the included 120mm AIO liquid cooler.
Despite coming with a significant factory overclock, the Sapphire Radeon RX 6900 XT LC still uses a pair of 8-pin PCIe power connectors. It's uncertain if the liquid-cooled variant still abides by the 300W TDP (thermal design power) limit as the normal Radeon RX 6900 XT, though. One would expect a more generous TDP, given the higher clock speeds on the Radeon RX 6900 XT LC.
The display outputs on the Sapphire Radeon RX 6900 XT LC, on the other hand, remains unchanged. Like AMD's reference design, the liquid-cooled variant retains support for four monitors. It offers the standard HDMI 2.1 port, two DisplayPort 1.4 outputs and one USB Type-C port.
Kabum has the Sapphire Radeon RX 6900 XT LC up for preorder at $4,662.40 or $3,368.41 in a single cash payment. Don't pay attention to the pricing since it probably includes VAT (value-added tax) and a huge retailer markup. Kabum claims that it'll start shipping Sapphire Radeon RX 6900 XT LC orders on June 30 so we could see an announcement from AMD very soon.