You could install it and still keep v6 , then just edit the path in the bat file or set the custom path setting in the launcher to reflect what version you want to use.
ie
v7
C:\Program Files (x86)\Java\jre7\
v6
C:\Program Files (x86)\Java\jre6\
I really don't see much speed difference though, perhaps less memory errors and somewhat smoother feel, but it could be the placebo effect. I even tried compiling a few builds with jdk7 to see if the compiler would help optimize but again I really haven't noticed a huge improvement
ie
v7
C:\Program Files (x86)\Java\jre7\
v6
C:\Program Files (x86)\Java\jre6\
I really don't see much speed difference though, perhaps less memory errors and somewhat smoother feel, but it could be the placebo effect. I even tried compiling a few builds with jdk7 to see if the compiler would help optimize but again I really haven't noticed a huge improvement
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