Provide some GPUs recommandations / hints

[lissyx]

It would be useful to help people scoping the requirements in term of GPUs to properly set expectations:

• how much VRAM required for training from scratch
• how much VRAM for transfer learning
• some ratio of GPU model / audio volume / training time

[lissyx]

Some data point on 2xRTX2080Ti 11GB VRAM

• trains from scratch flawlessly
• transfer learning
• training of ~1300h of audio data:
  • batch size 64
  • 1h per epoch

[ftyers]

Tesla k40m 11GB VRAM:

• Transfer learning ... for 10 hours training data approx. 20 mins per epoch
• Batch size 8