AMD has two desktop sockets on sale at the same time. AM4 launched in 2017 and runs Ryzen 1000 through 5000 processors. AM5 launched in 2022 and runs Ryzen 7000, 8000 and 9000. They do not mix: an AM4 CPU will not fit an AM5 board, and the two platforms use different memory.
The short version
- Pick AM4 if the budget is tight, you already own DDR4 memory, or you want the most performance per dollar today and do not plan to upgrade the CPU later.
- Pick AM5 if you want DDR5, PCIe 5.0 storage and graphics, and a socket AMD has committed to supporting with new processors for several more years.
What actually differs
| AM4 | AM5 | |
|---|---|---|
| Processors | Ryzen 1000 to 5000, including 5700X, 5800X3D, 5900X | Ryzen 7000, 8000, 9000, including 7800X3D and 9800X3D |
| Memory | DDR4 only | DDR5 only |
| PCIe | PCIe 4.0 on 500-series boards, 3.0 on older boards | PCIe 5.0 on X670E and B650E; 4.0 lanes on B650 |
| Chipsets | A520, B450, B550, X570 | A620, B650, B650E, X670, X670E, B850, X870, X870E |
| Cooler mounting | AM4 brackets | Most AM4 coolers fit AM5 with the stock backplate |
| Upgrade path | Ended with Ryzen 5000 | AMD has committed to AM5 support through at least 2027 |
When AM4 is the smarter buy
AM4 parts are cheap because the platform is mature. A refurbished Ryzen 7 5700X or Ryzen 9 5900X paired with a B550 board and 32GB of DDR4-3600 is still a strong 1440p gaming or editing machine. The Ryzen 7 5800X3D remains one of the best gaming CPUs ever sold on the socket. If you already have DDR4 sticks, AM4 lets you keep them, which can save the cost of a memory kit.
The trade-off is the dead end. Once you are on AM4 there is no faster CPU to drop in later. You will replace the board, memory and CPU together.
When AM5 is worth the extra cost
AM5 costs more up front because DDR5 and the boards are pricier, but it buys headroom. You can start with a Ryzen 5 7600 today and move to a Ryzen 7 9800X3D or a future chip with a BIOS update, keeping the board and memory. PCIe 5.0 M.2 slots matter if you move large video files; for pure gaming the difference between Gen4 and Gen5 storage is small.
Memory matters more on AM5. Ryzen 7000 and 9000 run best with DDR5-6000 CL30 and an EXPO profile enabled in the BIOS. Faster kits often run slower in practice because the memory controller drops to a 2:1 ratio.
Checklist before you buy
- Match socket to CPU. Ryzen 5000 means AM4 and DDR4. Ryzen 7000 or 9000 means AM5 and DDR5.
- Check the CPU support list. Older B450 and B550 boards may need a BIOS update for Ryzen 5000. B650 boards may need one for Ryzen 9000.
- Confirm the cooler. Ryzen 5 and most Ryzen 7 chips with a G or non-X suffix include a cooler. X and X3D chips do not.
- Buy memory as one kit. Two sticks sold together are tested as a pair. Mixing kits is the most common cause of a build that will not post.
Every processor and motherboard listing on KERNOVIQ shows the socket, supported memory and whether a cooler is included, so you can check compatibility before you order.