Dual R9700 Build Needs Lane Split

The core idea is sound for an academic lab, but the build is overbuilt in PSU and underbuilt in platform correctness. For dual 32GB GPUs, motherboard lane layout matters more than a flashy full-tower and a 1500W supply.

• –The MSI X870E Tomahawk is a poor fit if the second GPU lands on a chipset-connected x4 slot; that will bottleneck multi-GPU traffic and wastes the point of dual cards.
• –AMD lists the R9700 at 300W each with a 750W minimum PSU per card, so a quality 850W to 1200W ATX 3.1 unit is usually the smarter spend than a 1500W flagship.
• –The CPU choice is reasonable, but the platform should prioritize two CPU-attached PCIe 5.0 x8 slots, which is why workstation-leaning boards like the X870E Taichi Creator make more sense.
• –64GB system RAM is workable for inference, but if this lab will do dataset prep or heavier finetuning orchestration, 128GB would age better than the current expensive DDR5 kit.
• –The R9700 itself is a good match for local inference and multi-GPU scaling on Linux/ROCm, so the main question is not the GPUs, it is whether the rest of the box preserves their bandwidth.