have you also check the commited amount of memory, e.g. with help of resource manager ?
We discussed about similar case here: Performance Degradation with 1.14.5.0. Upgrade - #1743 by MichaMMA
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Some users report a huge memory usage, like a possible leak, with usage of slew ( or some kind of mods, e.g. fbw ). In case you run into strange high pagefile usage, then may be the trouble will start.