Been digging into the AI investment thesis lately and honestly, the numbers are wild. We're looking at AI spending potentially hitting nearly $5 trillion by 2033 — that's a massive runway for the right plays.

Obviously Nvidia comes up first when people talk about top AI companies to invest in. The GPU dominance is just insane right now. They're sitting on roughly 90% market share for AI GPUs, which basically means if you're training or deploying serious AI models, you're running on their chips. That kind of market position doesn't just happen by accident — it's a combination of performance and ecosystem lock-in that's pretty hard to replicate.

What gets me though is that despite the stock running hard, it's trading at 39x forward earnings. Yeah, it sounds expensive, but if this AI cycle really does play out over the next decade like everyone expects, Nvidia's probably going to keep growing double digits annually. That valuation premium could compress pretty quick when you factor in the growth runway.

But here's the thing — you can't just look at GPU makers. There's another layer to this whole infrastructure play that people sometimes overlook: cloud providers. Amazon Web Services basically owns this space with something like 30% of the global market. That's nearly as much as the next two competitors combined.

Why does that matter for AI specifically? Because developers need scale. They want the best hardware, the most geographic reach, fastest deployment. AWS can deliver all of that better than pretty much anyone else. When companies are planning their AI infrastructure, they're not just buying GPUs — they're buying into entire ecosystems, and Amazon's ecosystem is hard to beat.

The demand side is real too. Recent surveys show like 87% of companies planning to increase AI spending over the next year. That's not noise — that's actual capex flowing into this space at 20-30% annual growth rates.

So if you're thinking about the best AI stocks to invest in, you're basically looking at two different angles: the chip enabler (Nvidia) and the infrastructure backbone (Amazon). Both are positioned in ways that are pretty hard to dislodge. Worth keeping on your radar if you're building an AI-focused portfolio.