Hi there serious,
There is no real "ideal" connection speed, only the minimum. Everybody has a different type of internet speed and some have lag while using the same Internet speed as someone with no lag.
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I played on 0.92 download and 0.06 upload for a couple of years and didn't have problems. That's probably the worst connection you're going to see on the Internet for xbox live.
Hey there Serious!At the bottom of our "I'm getting randomly disconnected from Xbox Live" support article, you can see our recommended minimum speeds. Obviously faster is usually better (assuming it's a stable connection) but at least you can see the recommended minimum speeds.Let us know if you have any other questions. =)
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