An easy way to trim the cost of a lower end system is to skip Windows and install Linux, along with picking a less expensive AMD chip to power your system.  AMD has recently gifted us with new Kabini based Sempron and Athlon chips, the most expensive of which is available for less that $70.  For testing Phoronix used Ubuntu 14.04, the 3.14 kernel and Mesa 10.2 along with the Radeon 7.3.99 driver.  You will be glad to know that there were no compatibility problems with Linux whatsoever, all CPUs performed more or less as expected as you can see for yourself in the full review.

"It's been a busy past few days since AMD launched their "AM1" Socketed Kabini APUs. After the initial Athlon 5350 Linux review on launch-day, I did some tests involving a faster kernel and newer Mesa code along with some reference DDR3 memory scaling benchmarks for these APUs with Jaguar processor cores. Since then the Athlon 5150 and Sempron 3850/2650 APUs arrived."

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Processors