An “anonymous” security researcher has released a dump of the AMD 4800S Main Bios, Backup Bios, Rom and Fuses. This material could be useful for security researchers, in particular to learn more about the Xbox X. The PS5 scene might also benefit, to some extent.
What is the AMD 4800S and why does the hacking scene care?
The AMD 4800S is basically the APU used in the XBox Series X, with a deactivated GPU. It is believed that these APUs are “imperfect” Xbox chips that get repurposed by AMD. From eurogamer:
What if you could take the Zen 2 CPU cores found within Xbox Series X and PlayStation 5, transplant them onto a PC motherboard, install Windows and actually play PC games on them? Short of hacking the console and somehow crafting drivers for it, it’s a pipedream, but we can do the next best thing. AMD recently – and somewhat stealthily – released the 4800S Desktop Kit for Chinese OEMs. It’s a Micro ATX motherboard built around the Xbox Series X APU, shipping with 16GB of GDDR6 memory. The integrated GPU is disabled, but it is possible to install Windows on it, you can attach a decent graphics card – and yes, you can play PC games on an Xbox CPU.
The idea that this product even exists is baffling, but there is some logic to it. Not every PS5 or Series X chip that makes it off the production line is functional. There can be imperfections in the silicon that write off the chip – or parts of it. In this case, AMD chooses chips with defective GPUs, disables that graphics component and uses the CPU portion only. As you’ll see in the accompanying video – and indeed in the headline image – we can be sure it is Series X silicon because if you put the two chips side by side, they’re a match.
Something similar exists for the PS5, and that is the AMD 4700S. If that name rings a bell, that’s because the PS5 scene was excited about acquiring one of those not so long ago.
Hardware glitch attacks, firmware investigation, and other reverse engineering attempts could all yield information about that CPU, and, by extension, the Xbox series X. It is possible that potential vulnerabilities on the 4800S could be ultimately replicated on the Xbox X, assuming the chips and their firmwares are similar enough.
Furthermore, whatever the Xbox scene could learn about the similarities between the 4800S and the console’s APU, could potentially be replicated with the PS5’s 4700S. There’s a possibility that the 4700S and the 4800s have enough similarities that hardware/Firmware attacks on one system could be replicated on the other.
AMD 4700s CPU . Photo by @aschilling
Of course a lot of “ifs” in this, but if a respected hacker such as Flat_z believes it’s worth looking into this chip, there has to be good reasons.
I’ve just dumped AMD PSP ROM from 4800s Desktop Kit which shares the same APU as used in Xbox Series X (Arden, Sparkman). Now it’s a time to explore. 🙂 pic.twitter.com/JB8jqNcZ8u
— Aleksei Kulaev (@flat_z) February 28, 2024
Download AMD 4800S Bios
The archive includes MD 4800S Main Bios, Backup Bios, Rom, and Fuses.
You can download the files here. I expect they will disappear quickly.
source: Via Zecoxao
