Flan-PaLM 540B (Google) and PaLM (540B) (Google Research) are both frontier AI models. Flan-PaLM 540B was published in October 2022 and PaLM (540B) in April 2022.
Flan-PaLM 540B was trained on 2.5×10²⁴ FLOP, essentially the same compute as PaLM (540B) at 2.5×10²⁴ FLOP. Training compute is the closest available proxy for how much was invested in a model, though it says nothing on its own about how well that compute was spent.
These two models share no benchmark on which both have been scored, so no direct performance comparison is possible here. The specification table below is a comparison of inputs, not of results.