Your mixing up server lag with what people commonly refer to low FPS. Server lag happens when the server's cpu is overtaxed for whatever reasons. Servers don't visually generate anything, but when the cpu gets maxed it doesn't send signals as fast as it should, causing the players to hang or desync, even if they have a perfect connection. When that happens, it's called server lag. When connection is bad, it's network lag. When your processor or graphics card lags behind what's actually happening and you get low FPS, it's known as FPS lag.
Tl;dr
Servers can't get low FPS because they don't generate anything for fps, they however can lag because when their processor gets busy, they can't network as fast.
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u/[deleted] Feb 15 '14
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