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When Baldur's Gate 3 came out, Steam's overall bandwidth consumption went from around 18 Tbps to 146 Tbps
(reddthat.com)
From Steam's self-published stats.
Baldur's Gate 3 could not be preloaded and weighed in at 125 gigabytes on disk, so when the game left Early Access at 11am US Eastern yesterday, Steam's bandwidth utilization shot up 8x over a span of 30 minutes. I know personally, I saw my download hit over 600 Mbps across a 1 Gbps fiber connection.
Kudos to the system engineers at Valve. It is mind-boggling that they have built infrastructure that robust.
There wasn't a a pre-load for BG3 though, really. It was incompatible with their EA release.
Yes, hence the unusual spike in this case
I misinterpreted your original comment. We agree, haha.
And they had to make a bunch of posts and updates begging people to delete all saves and even completely uninstall the game. Hell, weeks ago they were flat out telling people not to even play it at all.
Which is all so silly. I really hope Valve took notice of all this, since it's such a huge release. They could definitely do with some improvements to this whole EA -> full release. Even as simple as having an option for two downloads (old EA version you can play now OR prerelease full version you cannot play until x time on y date).