FORTUNE -- When I talk to Silicon Valley types about Facebook's (fb) two recent mega-acquisitions, I find much more skepticism over the social network's $2 billion purchase of virtual reality headset maker Oculus VR than over its $19 billion purchase of mobile messaging start-up WhatsApp. Not so much because it's hardware vs. software, but because there is a widespread perception that the Oculus system causes users to experience headaches and nausea.
I can't personally speak to this issue of Oculus latency, in which the virtual reality software doesn't update in perfectly-timed sync with head or eye movements. But venture capitalist Chris Dixon believes the problem has been solved.
Now I know what some of you must be thinking: "Isn't Dixon a partner with Andreessen Horowitz, which led a $75 million Series B round for Oculus just last December, thus making it one of the main beneficiaries of Facebook's acquisition? And isn't Dixon one of the two Andreessen Horowitz representatives on the Oculus board? How on earth is he an unbiased observer?"
All of that is true. What also is true, however, is that Andreessen Horowitz actually passed on its original chance to invest in Oculus during its $16 million Series A round last June, namely because of the latency issue.
"The key breakthrough is they actually built a system with very low ' motion-to-photon' latency," Dixon explains. "They built this after the A. I've personally tried it a number of times. It solves the motion sickness issue (they've tested it on lots of people). It's one of the most amazing demos I've ever seen. We invested when we became convinced they could build consumer version in the near future with the same performance."
Again, I've never worn an Oculus headset -- let alone one with the most recent software. But something clearly changed between the first time Dixon wore one, and when the company was raising its Series B funding round. By the time Facebook came calling, perhaps it also got the headache-free version...
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