Are these system freezes caused of extremly high CPU use or by a complete system lockups/crash.
In case your system crashes then they are mostly caused by system, hardware, driver or Java problems or most likely a combination of these. There is not very much we can do about it in the Phex code.

I think the old GUI bug you are refereeing to was caused by deadlocks in Phex. But in that case they should not be related to system freezes. There are currently no known deadlock problems in Phex.

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