Everyone endeavors to build a PC that's somewhat future-proof, but most enthusiasts don't look at the motherboard beyond platform, PCIe generation, and basic slot compatibility. A small number perhaps delve into the finer details like the VRM, and very few think about looking at the BIOS chip.

The BIOS chip is an often overlooked detail, but it is an important consideration when it comes to determining your PC's longevity. Recently, motherboard manufacturers have taken to upgrading the storage capacity of BIOS chips. On AMD's current AM5 platform, a major shift is already underway, and the reason why has everything to do with how long your motherboard will remain useful.

What is a BIOS chip?

And what does it do?

The BIOS chip, commonly referred to as the SPI ROM in hardware circles, is a flash memory chip responsible for initializing your hardware every time you press the power button. Modern motherboards have been using UEFI firmware, which is the de facto evolution to the BIOS, but it still lives on the BIOS chip. Some of these chips have an 8-pin design, but it's not unusual to see higher-end motherboards use a 16-pin variant.

Besides boot instructions, the chip also stores the microcode, which is a processor-specific code that tells the motherboard how to communicate with a CPU with a given architecture. AMD systems use an AGESA code, and every new processor generation requires its own AGESA update. That's exactly why your motherboard requires a BIOS update if you switch to a processor with a newer architecture.

Over the years, capacity has grown linearly alongside complexity. While earlier BIOS chips shipped with 8KB or 64KB of memory, modern consumer boards now feature up to 16MB or 32MB chips. More recently, 64MB chips have entered the market, and they might just become the norm for the coming generation of motherboards.

The BIOS chip determines how long your PC lasts

Bigger is better, but there's a cost

For a case in point, you don't have to look beyond Socket AM4, which launched in 2016. AMD has supported their AM4 platform for nearly a decade now, and since then, Team Red has supported eight processor families, from the original Zen architecture all the way through Zen 4. AM4's longevity was one of the most distinct selling points. Who doesn't want to buy a board once and upgrade their CPU multiple times without pulling apart their entire build?

There was, however, a physical bottleneck to the upgrade trajectory. With the launch of Zen 2 processors, many motherboards still shipped with 16MB BIOS chips. To make room for the new AGESA code, some manufacturers had to improvise and drop support for older processors from the firmware. On some boards, like the 300 and 400 series, MSI even had to do away with their flagship "Click BIOS 5" interface to replace the aforesaid with a "Lite" version. When that wasn't enough, MSI had to strip out features like RAID support and A-XMP profiles as well.

Higher-capacity chips were previously limited to higher-end SKUs, which did detract those looking to build a budget or mid-range PC. For those focused on higher specs or ones with a focus on a future-proof build, the expenditure would be easily justifiable, however.

Chip capacities are changing, and that's a good thing

More life on the same motherboard benefits everyone

AMD's latest AM5 platform rolled out in 2022 with the Ryzen 7000 series processors and has since grown to support Ryzen 8000G and Ryzen 9000 families. As Team Red has previously hinted at supporting AM5 through at least 2027, the platform is more than likely to add support for the upcoming Zen 6 processors.

It is this very roadmap that is driving manufacturers to move to larger BIOS chips. If AMD follows the precedent set by their AM4 support, then it's reasonable to assume that AM5 would continue to house newer chips for a while. To that end, motherboard manufacturers must act accordingly. The more processor generations a platform has to support, the more storage the firmware needs.

Some large motherboard vendors have already begun the work. At CES 2026, ASUS signaled their intention by refreshing their lineup with ROG Strix, TUF, and ProArt "Neo" motherboards, and while AI features stole the headlines, the Taiwan-based manufacturer also doubled the ROM capacity from 32MB to 64MB, stating, "Future BIOS updates might require us to allocate more of this space for CPU support."

Should BIOS chip capacity affect your purchase decisions?

From a future-proofing standpoint, it is well worth a consideration. If you are planning to upgrade your CPU down the line, or perhaps reuse the board with an older processor for another reserved build, a higher-capacity chip reduces the risk of losing backwards compatibility when new BIOS versions arrive. It is also important to note that smaller chips can also compel manufacturers to cut conveniences like on-board Wi-Fi drivers (as manufacturers like ASUS state) to free up space. Cost is also a noteworthy consideration, but for longevity-minded builders, it's worth prioritizing.