The Intel Atom E3825 "Bay Trail" dual-core SoC was found on the AAEON EMB-BT1 mini-ITX board that we began benchmarking this weekend on Phoronix. Its full review is still forthcoming but while writing the article about upgrading the Linux kernel and Mesa Intel driver, I went ahead and ran some OpenGL performance benchmarks each step of the way.
All the performance benchmarks were handled via the Phoronix Test Suite. Thus if you want to compare your own system's hardware or software configuration against the results about to be shown, simply run phoronix-test-suite benchmark 1404064-KH-UBUNTU14050. Ubuntu 14.04 was tested in its out-of-the-box configuration on this platform (Mesa 10.1 + Linux 3.13), then when upgrading to the Linux 3.14, and lastly when using the Linux 3.14 kernel plus Mesa 10.2-devel.
For this particular system there wasn't much to be gained in terms of performance out of the newer kernel and Mesa than what's being shipped in Ubuntu 14.04 LTS, but for other GPU configurations you will certainly be able to see a difference -- namely Intel Broadwell and newer AMD Radeon GPUs. You can see more of these Atom E3825 benchmarks via this result file.