Question / Help Stream Settings Help

So my PC specs are as follows
AMD FX-8320 @ 4.0Ghz (liquid cooled and can clock higher easily)
16GB 1600mhz DDR3
Sapphire Radeon 7870Ghz Edition

My upload is ~4800kbps.
I use ~3000kbps to stream, can go up if need be.
I stream to Ashburn,VA server.
Native Resolution 1920x1080
Downscale to 1280x720 using lanczos filter.
I also use the faster preset.

I have 2 questions with this setup. During my stream all of the cores on my processor are under 40% load no matter what(usually 30%, so no strain there), never going anywhere the 90% I see some people here speak of...

Would I be able to pull off 720p60 with a 3500kbps bit rate and would it be crisp?
Also, with my overclock and cooling setup can I pull off a slightly better cpu preset?

Thanks
 
Because I'm at work and when I get home I start my stream up. Not a lot of time to test sadly. Working full time and then going home to stream every night leaves about enough time to shower in my daily life. Lol. I'm just asking in general if these options are viable.
 
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