2 GB might not be enough to train FastPitch but you might squeeze by with gradient checkpointing and gradient accumulation to reduce memory usage. A 1 GB card will certainly be too little since the model parameters are 512MB and you need at least twice that to also store the gradient. If it doesn't work you could shrink the parameters down and train a lower quality model from scratch. However, it seems the GT430 supports CUDA 2.1 and the 750Ti supports 5.0. 2.x capability was removed in CUDA 9 and 6.x removed in CUDA 10. If you're lucky you might be able to get them to still work by compiling PyTorch and Tensorflow with the CUDA version you need, but I wouldn't bet on it.
I'd recommend using at least Python 3.7 and Tensorflow==2.3.0 since Spleeter requires that specific version. If someone has a newer GPU with at least 6 GB they'll have to download a Tensorflow 2.3.0 wheel with CUDA 11.1 because Tensorflow only supported 10.1 until version 2.4. A Tensorflow 2.3.0 + CUDA 11.1 wheel for Python 3.8 is available here: https://github.com/davidenunes/tensorflow-wheels
Again this is only necessary if you have a newer GPU with at least 6 GB. Spleeter will run fine on the CPU.
I use Python 3.7 and don't feel like compiling a Tensorflow 2.3.0 wheel for it so I just modified Spleeter's requirements.txt to support tensorflow==2.4.0 and numpy>1.16.0,numpy<=1.19.5 and installed it from source. Spleeter will still work and output the clean voice clips but crash after finishing. This error can be patched by commenting out the del
function in spleeter/separator.py:135 since Tensorflow 2.4 closes the session automatically.
I'm using PyTorch 1.8.0 with CUDA 11.1 since it supports the full capabilities of my GPU. To use either PyTorch or Tensorflow easily you'll need at least a 4th generation i3 which has AVX2 support. Otherwise you'll have to look for community pip wheels compiled without AVX/AVX2 for your specific version of Python. Older versions of PyTorch are compatible with most deep learning models but lack the newer torchaudio which is an amazing library for processing and training on audio that will certainly start seeing some use soon.
Lastly, Clipchan needs to be updated to support the latest Spleeter version which completely changed everything again, but that'll be an easy fix. I'll patch it tonight.