Schwarzgerät III: Difference between revisions

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As I detailed regarding [[Schwarzgerat II]], the 3990X is an amazing achievement in chip design and fabrication, but I believe it to be severely starved for many tasks by its memory bandwidth; with its four memory channels populated, the ThreadRipper 3990X can hit about 90GB/s from fast DDR4; its Epyc brother can pull down ~190 through its eight channels. For my tasks, it's rare enough that I can drive all my 32 cores; with the 3990X, I'd be paying twice as much to hit full utilization less often, and be unable to bring full bandwidth to bear when I did.
As I detailed regarding [[Schwarzgerat II]], the 3990X is an amazing achievement in chip design and fabrication, but I believe it to be severely starved for many tasks by its memory bandwidth; with its four memory channels populated, the ThreadRipper 3990X can hit about 90GB/s from fast DDR4; its Epyc brother can pull down ~190 through its eight channels. For my tasks, it's rare enough that I can drive all my 32 cores; with the 3990X, I'd be paying twice as much to hit full utilization less often, and be unable to bring full bandwidth to bear when I did.


I absolutely 🖤 my 3970X, though. Bitch screams. Anyone overclocking on Linux should be aware of [https://www.linux.org/docs/man8/turbostat.html turbostat].
I absolutely 🖤 my 3970X, though. Bitch screams. Anyone overclocking on Linux should be aware of [https://www.linux.org/docs/man8/turbostat.html turbostat]. The 3970X supports 88 lanes of PCIe 4.0, of which the TRX40 chipset consumes 24, leaving 64 for expansion devices. I've got 16 (GPU) + 16 (Hyper X) + 2x8 (LSI cards) + 12 (M.2 onboards) for 60 total, coming in just under saturation.


===Power===
===Power===