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quant choices for 70B local with PyTorch - Printable Version

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quant choices for 70B local with PyTorch - benchplease - 10-17-2026

Spent some time on this today and wanted to compare notes.

I've gone back and forth between PyTorch and PyTorch for Qwen. The interesting difference for me has been speculative decoding.

Trying to avoid rebuilding the whole thing twice.


Re: quant choices for 70B local with PyTorch - bytehall - 10-18-2026

Need a little more detail here. Is this local-only or are you routing anything externally?


Re: quant choices for 70B local with PyTorch - vrambandit - 10-18-2026

Did a small comparison this afternoon. The issue went away once I changed one setting and restarted the stack cleanly. I expected the model choice to matter more than it did.


Re: quant choices for 70B local with PyTorch - fusedtinker - 10-18-2026

Quote:Did a small comparison this afternoon. The issue went away once I changed one setting and restarted the stack cleanly. I expected the model choice to

That matches what I was seeing. I don't think your conclusion is far off. The biggest change for me was simplifying the stack instead of adding one more optimization layer.

I'm happy to test one more variant if you want a second data point.


Re: quant choices for 70B local with PyTorch - bytehall - 10-18-2026

Not sure I agree there. I wouldn't optimize around that first. On my side the bigger swing came from the runtime and not the model. Worth testing the simpler explanation before adopting the more interesting one.


Re: quant choices for 70B local with PyTorch - cacheplane98 - 10-18-2026

following this because I'm in the same boat.


Re: quant choices for 70B local with PyTorch - turbosupply83 - 10-18-2026

Quote:following this because I'm in the same boat.

A couple things I'd check first. Start by verifying the driver/runtime combo, then test with a smaller prompt, then look at router policy. Not glamorous advice, but repeatable baselines save a lot of time.


Re: quant choices for 70B local with PyTorch - benchplease - 10-18-2026

I don't think that's the whole story. I've seen people blame HBM constraints when the real issue was much more mundane.


Re: quant choices for 70B local with PyTorch - northquill - 10-18-2026

Thanks, that helps. I ended up in about the same place using TensorRT-LLM. Worth rechecking your defaults though, because one bad assumption can make the rest of the thread look confusing.


Re: quant choices for 70B local with PyTorch - phasestream53 - 10-19-2026

What worked for me was pretty simple. On B200, the easiest win is often to back off the aggressive settings and see whether the problem survives. Once you know the plain path works, then add the faster path back in piece by piece.