The giant aluminum X was first seen at Bill Gates' GDC 2000 keynote.
Microsoft's original Xbox was pretty big, but the prototype was even bigger.
Microsoft has proudly displayed its original Xbox prototype at its company's visitor center in Redmond, Washington.
The massive aluminum console -- much more "X" than "box" at this point -- was first seen when former Microsoft boss Bill Gates and Xbox cofounder Seamus Blackley showed off the hardware at GDC in March 2000, Eurogamer notes.
Xbox social marketing manager Graeme Boyd shared a shot of the prototype at the Microsoft Visitor Center on Saturday.
The original Xbox prototype from Bill Gates’s GDC 2000 keynote is on display at the new Microsoft Visitor Centre.
— Graeme Boyd (@AceyBongos) June 30, 2018
Absolute unit. Love it. pic.twitter.com/KMxOPNmTTJ
"The original Xbox prototype from Bill Gates's GDC 2000 keynote is on display at the new Microsoft Visitor Centre," he wrote. "Absolute unit. Love it."
Each prototype unit cost $18,000 to make because they were milled from solid block of aluminium, Dean Takahashi wrote in Opening the Xbox -- as cited by Eurogamer.
Blackley confirmed that the chunky prototype wasn't just for show and actually worked.
"This was the showcase unit to show partners and press. It worked. [There were actually several, and they travelled the world. I lugged these damn things over every continent literally.]" he tweeted.
The original @xbox prototype hardware on our @snapchat story pic.twitter.com/5IweH06lBS
— Aaron Greenberg (@aarongreenberg) November 15, 2016
The world's last encounter with the prototype was a November 2016 Twitter video from Aaron Greenberg, the Xbox marketing boss.
Microsoft may have moved on from their original console -- launching the Xbox 360 in 2005 and the Xbox One in 2013 -- but gave its blessing for the huge original Xbox "Duke" controller to the relaunched in March.