How We Tested & Bandwidth
AMD has supplied us with its top-end FX-8350 processor for testing. Thankfully, the FX range is unlocked and the Asrock Fatal1ty 990FX motherboard allowed us to enable just six cores, making it possible to emulate the FX-6300. This board also allows customization of the Turbo Core and Max Core multiplier for accurate results. Unfortunately, because the FX-4300 processor features a smaller 4MB L3 cache we're unable to emulate that processor.
AMD AM3+ Test System Specs
- AMD FX-8350 (4.00GHz)
- AMD FX-6300 (3.50GHz)
- AMD Phenom II X6 1100T (3.30GHz)
- AMD Phenom II X4 980 (3.70GHz)
- AMD FX-8150 (3.60GHz)
- AMD FX-8120 (3.10GHz)
- AMD FX-6100 (3.30GHz)
- AMD FX-4170 (4.20GHz)
- x2 4GB G.Skill DDR3 PC3-14900 (CAS 8-9-8-24)
- Asrock Fatal1ty 990FX Professional (AMD 990FX)
- OCZ ZX Series 1250w
- Crucial m4 256GB (SATA 6Gb/s)
- Gigabyte GeForce GTX 580 SOC (1536MB)
Software
- Microsoft Windows 7 Ultimate SP1 64-bit
- Nvidia Forceware 306.23
Core i7 Test System Specs
- Intel Core i7-3960X Extreme Edition (3.30GHz)
- Intel Core i7-3820 (3.60GHz)
- x4 2GB G.Skill DDR3-1600(CAS 8-8-8-20)
- Asrock X79 Extreme11 (Intel X79)
- OCZ ZX Series (1250w)
- Crucial m4 512GB (SATA 6Gb/s)
Software
- Gigabyte GeForce GTX 580 SOC (1536MB)
- Microsoft Windows 7 Ultimate SP1 64-bit
- Nvidia Forceware 306.23
Intel LGA1155 Test System Specs
- Intel Core i7-3770K (3.50GHz)
- Intel Core i5-3470 (3.20GHz)
- Intel Core i3-3220 (3.30GHz)
- Intel Core i7-2600K (3.40GHz)
- Intel Core i5-2500K (3.30GHz)
- x2 4GB G.Skill DDR3 PC3-14900 (CAS 8-9-8-24)
- Asrock Z77 Extreme9 (Intel Z77)
- OCZ ZX Series 1250w
- Crucial m4 256GB (SATA 6Gb/s)
- Gigabyte GeForce GTX 580 SOC (1536MB)
Software
- Microsoft Windows 7 Ultimate SP1 64-bit
- Nvidia Forceware 306.23
AIDA64 demonstrates that AMD hasn't changed anything to improve the memory subsystem of the Piledriver FX processors. Although the FX-8350 had 4% more read bandwidth at its disposal, keep in mind that it is clocked 11% higher than the FX-8150. Compared to the Core i5-3470, the FX-8350 was 24% slower when measuring read bandwidth and 44% slower in write bandwidth.
We found AIDA64's reported L2 cache performance to be odd, as the new Piledriver FX CPUs had a similar write performance to Bulldozer while their read results were halved. Either something has gone drastically wrong with the Piledriver processors or, as is the more likely explanation, AIDA64 needs to be updated. In either case, we'll be looking into this over the next few days.