Solving a problem with hardware either solves a problem or replaces the thing that fixed the problem before. Solving a problem with software is usually (if not always) making computers better or easier to use. The underlying difference is how clear the change is in the user's life.
The much larger cost to develop and produce hardware like some in the comments have been discussing leads us to value hardware much more significantly than software. It might be due to iTunes, Java, and Windows update making people mad when they waste their time, or have their computer shut down on them in the middle of their work, but there is a significant bias.
My point was: if $50M is your maximum potential - if everything goes perfect - it'd be pretty hard to get some interest from VCs.
For their math to work out, they need at least the potential for an exit a few orders of magnitude more than their investment. If VC rounds start at $1M, a max potential of $50M will not be taken into consideration so easily ?