Best not to say "Try it in Linux" on Slashdot, you're a lot more likely to run in to someone who already has. My laptop and server are exclusively Linux and my desktop dual-boots. Ubuntu LTS all around, 14.04.1 on the desktop/laptop and I haven't gotten around to upgrading the server from 12.04.5 yet. AMD even lost performance per clock compared to themselves with their recent chips.
My home server previously ran a Phenom II X4 945, a 3 GHz quad core released in mid-late '09. That motherboard blew up after a power event so I switched to an A10-7850K, a 3.7-4.0 (turbo) GHz quad core released in January of this year. It's both faster clocked and a full four years newer, plus I threw double the RAM at it since I had to get new sticks anyways for DDR3 vs the old DDR2, yet somehow it's slower in the real world. My usenet downloads parcheck/extract slower, my Minecraft server bogs down more often, and it can't even manage to proxy Steam traffic at the full 100mbit/sec my internet connection allows.
As for Phoronix, how's this one? The very processor I'm running, the top model of the latest core AMD has released.
In looking at the results the AMD A10-7850K is supposed to be in line with the Intel Core i5 4670K according to AMD's expectations. However, with Ubuntu Linux on this hardware the Core i5 4670 (non-K) was generally running noticeably faster than the Kaveri APU. This is a big deal since the Kaveri APU sells for $190 USD where as the i5-4670 is not much more at a price of about $218.
It barely holds with the Core i3s on average.
I have historically defaulted to AMD. My last Intel outside of laptops was a 300 MHz Pentium II. I regret going with AMD for the server and unless they pull something huge out of their ass in the near future I'll be changing my desktop over as soon as the prices drop on the now last-gen Intels.