WTF?! For the previous couple of days, the laptop {hardware} microcosm of the web has been awash with theories about an AMD Ryzen 7 7800X that appeared in the (*7*) database on October 27. It hadn’t been seen, heard, or rumored wherever beforehand, which is sort of unprecedented. Had AMD actually made a 10-core Zen 4 CPU with out anybody realizing?
Nope. Chips and Cheese has come clear. They fooled (*7*) with a phony title by spoofing the CPUID on what was really a Ryzen 9 7950X system. They additionally disabled six cores and diminished the precision enhance overdrive clock by 350 MHz to make it look (and carry out!) like a center floor between the very actual 7700X and 7900X. I’m wondering what AMD’s engineers thought once they noticed the ‘leaked’ processor.
The Chips and Cheese workforce admitted to altering the CPU’s title with an inside benchmarking software initially designed to seek out bottlenecks in CPU design. It’s been accessible on GitHub this complete time and nonetheless is, so if you wish to pull off an identical prank, tag us on Twitter once you do. Here are some enjoyable, definitely-real processors that appeared in the (*7*) database this week.
7800X
7830U
youtube.com/watch?v=dQw4w9WgXcQ | (*7*)
Chips and Cheese’s software, known as PMCReader, abuses the approach benchmarking instruments like (*7*) learn a CPU’s title on AMD programs. The CPUID for AMD processors is saved throughout six MSRs (Model Specific Registers) that may every comprise eight ASCII characters (so no emoji, sadly). Programs can learn the CPUID by accessing these six registers. These MSRs are publicly accessible in AMD’s PPR (Processor Programming Reference) papers, which clarify that the BIOS units them at boot.
Some AMD CPUs as previous as Bulldozer permit them to be written to arbitrarily, though some architectures are extra okay with title adjustments than others. Some MSRs might be modified later by packages with admin privileges, together with these six registers. With PMCReader, you may give your CPU any title with as much as 47 characters: try Chips and Cheese’s hilarious instance under.
Chips and Cheese say their software can idiot (*7*), Cinebench, AIDA64, HWMonitor, the Blender Benchmark, and nearly the whole lot else they’ve examined. So far, the solely exceptions to the rule have been HWiNFO and BenchMate (which borrows HWiNFO’s instruments) as a result of they supply the CPUID from a extra elementary stage, very like the BIOS does.
It’s really been doable to spoof these benchmark instruments for a very long time with extra than simply foolish names. Virtualization software program like VMWare or CPUs from non-major producers can falsify the CPU mannequin, household, stepping, and producer in case you have the requisite experience. However, with PMCReader, anybody can change the CPUID on an AMD CPU. From now on, it’s going to be powerful to inform if a leaked benchmark outcome from a web based database is actual — which provides to the enjoyable if you happen to ask me.
https://news.google.com/__i/rss/rd/articles/CBMiVWh0dHBzOi8vd3d3LnRlY2hzcG90LmNvbS9uZXdzLzk2NDg5LWdlZWtiZW5jaC10cmlja2VkLXJ5emVuLTctNzgwMHgtZG9lc250LWV4aXN0Lmh0bWzSAQA?oc=5
