For each 100-watt Trinity variant AMD also offers a more energy efficient version with a TDP of 65 watts. The A8-5500 is the more economical counterpart of the A8-5600K. They are identical in every specification except for the clock rate of the execution cores. The 65-watt A8 model clocks them at 3.2 GHz (3.7 GHz in turbo mode). Its Radeon HD 7560D graphics core is identical to the A8-5600K’s and works at a frequency of 760 MHz. So, however odd it may seem, the 35% TDP reduction is achieved by lowering the clock rate of the x86 cores by only 200-400 MHz.
The A8-5500 normally works at 3.5 GHz. When the load is high, its speed is lowered to 2.9 GHz, even though AMD doesn’t make this fact obvious in the specifications.
The A8-5500 is not an overclocker-targeted product and its frequency multipliers are all locked. Overclocking its x86 cores, graphics core or memory controller may only be done by changing the clock generator’s frequency.
Starting from the A6 series, the Trinity family includes APUs with a greatly reduced x86 part. For example, this A6-5400K model has only one Piledriver module with two x86 cores for integer operations and one floating-point unit. The capacity of the shared L2 cache is reduced to 1 MB, too. Thus, the total amount of L2 cache in this APU is only one fourth that of the A10 and A8 APUs.
The graphics capabilities of this Trinity modification have been cut down as well. The graphics core integrated into the A6-5400K is called Radeon HD 7540D. Architecturally, it is exactly one half of the Radeon HD 7660D available in the A10 series.
The A6-5400K doesn’t look deficient in its clock rates only. The graphics core works at a standard 760 MHz while the execution cores, at 3.6 GHz (3.8 GHz with Turbo Core technology). As opposed to the quad-core Trinity APUs, the A6-5400K easily accelerates to 3.8 GHz and keeps on going at that frequency continuously at high loads. But, like every other Socket FM2 APU, it eventually slows down, to 3.2 GHz, when doing hard computing work.
It’s hard to tell what overclockers might be interested in the A6-5400K but it comes with unlocked frequency multipliers. We can only suppose that this capability is meant to make it more competitive against Intel’s Pentium and Celeron processors which cannot be overclocked at all. By the way, the A6-5400K is the only overclocker-friendly Trinity with a TDP of 65 watts.
The A6-5400K may seem the ultimate simplification of the original Trinity design, yet the A4-5300 is even simpler than that. This APU has much lower specs. It only has one dual-core Piledriver module with a shared 1MB L2 cache and its clock rate is 3.4 GHz. The turbo mode boosts this clock rate by a mere 200 MHz, but the worst thing is that the maximum memory frequency the A4-5300 supports is DDR3-1600. It’s not just a formal line in its specs. If you try to increase the speed of DDR3 SDRAM above 1600 MHz, the APU will not start up. Therefore, the A4-5300 is the only APU we have to benchmark with DDR3-1600 rather than with faster DDR3-1867 SDRAM.
AMD has been even crueler about the graphics core here. The one incorporated into the A4-5300 is called Radeon HD 7480D, works at 723 MHz and has only 128 shader processors. In other words, there are only two SIMD engines active in the A4-5300 out of the six available in the original design. Fortunately, AMD didn’t turn off video encoding technologies in this junior APU as Intel did, so the A4-5300 is quite suitable for multimedia applications, especially as its actual heat dissipation should be very moderate, considering its relatively low clock rates.
The A4-5300 mostly works at 3.6 GHz, but slows down to 3.0 GHz at high loads.