Clarify the details about the motherboard and its dual GPU configuration.
Clarify the details about the motherboard and its dual GPU configuration.
Hey everyone, I'm using a Ryzen 3rd Gen CPU paired with an MSI B450 Gaming Plus Max that supports two graphics cards. I'm planning to run multiple cards mainly for color calibration across two monitors. Based on what I've learned, AMD's Radeon series uses one LUT while Firepro has two—similar to Nvidia. The two cards won't be linked together. I think a single strong GPU will handle everything through Nvidia's settings, and the other card in slot 4 would just run at its original speed of 3.0x16 unless I switch it to match the first card. The motherboard specs for multi-GPU are shown in the picture. So, when I put a card in slot 4, will the first card automatically drop to 3.0x8 or 3.0x4?
Slot 1 will consistently use PCIE 3.0 x16 (applicable to Ryzen 3rd gen CPUs except 3200G and 3400G). M.2 slots will always support PCIE 3.0 x4. The remaining PCIe lanes are provided by the chipset instead of the CPU. Slot 4 operates at PCIE 2.0 x4 speeds (approximately 2GB/s), which may limit a modern graphics card depending on your needs. Could you provide your motherboard model and type for verification?
Thanks! I'll stay stable as long as slot 1 runs at full speed. The chip that fits in slot 4 might be either a GTX 660 or 640; it’s mainly for connecting to another screen and won’t do anything else, so I’ll likely pick the 640 to cut power usage. I’m really relying on it for the extra LUT. I don’t have anything in slots 2, 3, or 5, which means it will ring at 2.0x4 speed. Here’s the link to the motherboard specs. Thanks again!
The first PCIe X16 port offers either 16 or 8 PCIe lanes based on the CPU. CPUs with built-in graphics provide only 8 lanes. The nearest M.2 connector to the CPU socket delivers 4 lanes, while other PCIe slots draw from the chipset. A B450 chipset supports 6 PCIe 2.0 lanes, which the motherboard can allocate to PCIe slots or extra M.2 connectors. A second physical PCIe X16 slot exists but functions electrically as an x4 port with PCIe 2.0 speed (500 MB/s instead of ~970 MB/s for PCIe 3.0). To achieve four PCIe lanes, most of the other x1 slots must stay empty; otherwise, the second slot may be downgraded to x1. The configuration shown—PCIe X4 plus one PCIe 6x1—provides five lanes total.
You should ensure your graphics card supports several output ports... it makes sense to use a different HDMI or DisplayPort cable for the second monitor instead of relying solely on the existing setup.
I don’t assume you own a Ryzen 3000 CPU; let me know which model you have. If it’s not the 3200G or 3400G, here’s how the connections will work: The PCIE slots you’re planning to use are spread across different sections of the system—main slot on CPU lanes, other chipset lanes for PCIE, and an M.2 slot elsewhere. This setup means each slot operates at its respective speed when used together with the above CPU: - PCIE slot 1 will run at 3.0x16
- PCIE slot 4 will run at 2.0x4 (2GB/s)
- M.2 slot will be 3.0x4 or support SATA 6Gb/s, with ports 5 and 6 disabled during operation.
I also asked about your video card usage since that’s a common point of confusion regarding PCIe lane requirements.
Because a video card is limited to just one LUT for the whole unit, it can only work with a single calibrated color display. This explanation comes from Xrite, a company specializing in color calibration. Regardless of how many ICC profiles Windows offers, the card’s capabilities are still capped by its LUT count. Recently I spoke with Nvidia and learned that none of their GeForce models support LUTs. That means I can’t calibrate any monitor, which is really disappointing. My RX 2070 is my primary choice for graphic work, and the price was significant—thank you for your understanding. This situation is frustrating, especially since AMD’s Radeon line offers more LUT support.