Ryzen 9 5900X Wakes Up on Old Budget Board ASRock A320
The information has appeared on the Web that gives hope that the new AMD Ryzen 5000 (Vermeer) series processors will still be able to work on old motherboards with AMD 300 series chipsets. Recall that the new chips based on the Zen 3 architecture are still officially compatible only with motherboards based on AMD X570 and B550. In January next year, support will be received for motherboards based on the X470 and B450 logics, which according to the manufacturer, 300 series chipsets should not work with Ryzen 5000.
However, one of the users of the Chinese forum Chiphell posted a screenshot of the CPU-Z program, as well as a screenshot of the BIOS of an ASRock A320M-HDV R4.0 motherboard running with a 12-core Ryzen 9 5900X processor after modifying the motherboard microcode.
The user has hidden the BIOS version itself, so it is still not possible to say with certainty whether we are talking about the official beta version of the firmware from ASRock, or whether it is its own modification.
Recall: A320M-HDV R4.0 is a budget board with an average price of about 4000-5000 rubles and uses a simple six-phase processor power subsystem. Nevertheless, it quite officially can work even with the 16-core Ryzen 9 3950X based on the Zen 2 architecture.
Unfortunately, nothing is known about how the A320M-HDV R4.0 behaves with the new Ryzen 5000 processor family since the user Chiphell did not provide any comments and results of synthetic tests. But obviously, there are limitations, for example, the old board most likely does not support PCIe 4.0 and other new features inherent in more modern motherboards.
Another user on the Overclock.net forum reported that a friend of his was able to run one of the Ryzen 5000 processors on a Gigabyte motherboard with an AMD X370 chipset. According to him, there is a beta version of the BIOS code for this motherboard, adding compatibility with Zen 3. Whether this firmware is provided by the manufacturer of the motherboard or is independently modified by the user is not reported. But the source claims that despite the lack of PCIe 4.0 support, the bundle from the old motherboard and the Ryzen 5000 series processor works flawlessly.
The main factor limiting support for new processors in old motherboards with Socket AM4 is the small size of the SPI ROM chip, which contains the BIOS firmware. The Socket AM4 platform was introduced in 2016, and since then AMD has released many processors for it, including families of hybrid models. It is impossible to fit the code with support for each processor inside a small SPI ROM. Even in the more modern 400-series motherboards, manufacturers will have to make certain trade-offs, such as depriving the motherboard of compatibility with older processors, in order to add support for new ones. This practice has already been used in the past.
If Socket AM4 motherboards based on 300 series chipsets do receive official (or unofficial) support for Ryzen 5000 chips, then their owners will surely have to face various restrictions of this kind.
