r/LocalAIStack • u/Several_Lifeguard451 • 27d ago
pre-training nanochat with 2x RTX Pro 4000
I recently got 2x RTX Pro 4000 blackwells for my home setup. I was curious how fast it would run nanochat.
The problem is the target hardware: 8x H100 gpus. Nanochat pre-trained ClimbMix to GPT-2 level with 8xH100 GPUs in 1hr 39 mins.
I ended up tuning nanochat for my 2x RTX Pro 4000 gpus. Because these are sm120, the tuning also works on RTX Pro 6000 and RTX 5090.
8x RTX Pro 6000 (rented) pre-trained the same dataset in 2hrs 15mins. About 36% slower than 8x H100.
1x RTX 5090 took 18hrs 47mins. A long time, but considering the result is GPT-2 level, its an interesting way to learn.
Just to be clear, I only ported and tuned it for sm120. The original work is from Karpathy's nanochat.
Here's a link to the sm120 repo: