Crypto Miners Driving High Demand for AMD CPUs with Big L3 Cache

Now that crypto miners and their scalping ilk have succeeded in taking all of our precious GPU stock, it appears they’re now setting their sights on one more thing gamers cherish: the AMD CPU supply. According to a report in the UK’s Bitcoin Press, part of the reason it’s so hard to find a current-gen AMD CPU for sale anywhere is because of a crypto currency named Raptoreum that uses the CPU to mine instead of an ASIC or a GPU. Apparently, its mining is sped up significantly by the large L3 cache embedded in CPUs such as AMD Ryzen, Epyc, and Threadripper.

Raptoreum was designed as an anti-ASIC currency, as they wanted to keep the more expensive hardware solutions off their blockchain since they believed it lowered profits for everyone. To accomplish this they chose the Ghostrider mining algorithm, which is a combination of Cryptonite and x16r algorithms, and thew in some unique code to make it heavily randomized, thus its preference for L3 cache.

In case you weren’t aware, AMD’s high-end CPUs have more cache than their competitors from Intel, making them a hot item for miners of this specific currency. For example, a chip like the Threadripper 3990X has a chonky 256MB of L3 cache, but since that’s a $5,000 CPU, miners are settling for the still-beefy Ryzen chips. A CPU like the Ryzen 5900X has a generous 64MB of L3 cache compared to just 30MB on Intel’s Alder Lake CPUs, and just 16MB on Intel’s 11th-gen chips. Several models of AMD CPUs have this much cache too, not just the flagship silicon, including the previous-gen Ryen 9 3900X CPU. The really affordable models, such as the 5800X, have just 32MB of L3 cache, however.

According to the Raptoreum Mining Profitability Calculator, just one AMD 5950X can generate 181 Raptoreum a day, which at its current price is around $4. This means you could theoretically pay off the cost of the CPU in roughly six months, electricity costs aside. AMD CPUs are also favorable in this situation not just because of their L3 cache but also because of their excellent performance-per-watt, as they have been more efficient than Intel’s chips for some time now, though of course the company hopes to change that with Alder Lake. Still, Bitcoin Press notes, “Rough power consumption estimates for Ryzen 9 3900X system is rated at 190W with OC settings,” which is likely better than any CPU currently on the market.

Making matters potentially even worse, AMD’s next update for its Ryzen CPUs will include adding V-cache, which is vertically stacked L3 cache on-die, with 64MB per chiplet. These L3 upgrades will certainly makes its chips even more desirable for Raptoreum miners, assuming the currency still exists when the updates arrive in early 2022.

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