OP, All the symptoms you mention have been reported as bugs by various people. Check out the PC bug reporting forum. The stuttering exiting SC affected me, however since downgrading from a 4GB RX 480 to a 2GB GTX 960, the stuttering has gone totally. Dxdiag did report a memory leak in ED64. Maybe it only has an effect on cards with more ram, I dunno...
I have RX 480 8 GB after market OC version (Red Devil), its similar to 1070, I rly love it, it works so good with other games, not ED tho
And yes I've been checking bug section of the forums from time to time, but had not found anything that would help me sadly.. Bummer.
I hope that commanders update will solves this, but probably wont hold my breath
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Hard to say without seeing a "live" performance monitor on your machine. This could be due to a number of things. Also, if you have a fixed-size page file rather than a system-managed page file, this can also be a contributor.
Fixed-size page file? Whats that