Phenom CPU and 790FX Chipset

So exactly what is launching today? As we mentioned earlier, Phenom is debuting at speeds of 2.2GHz and 2.3GHz. The 2.2GHz chip is named the Phenom 9500 and is priced at $251, while the 2.3GHz CPU is branded as the Phenom 9600 and carries a price tag of $283. Of course, keep in mind that these are the prices AMD charges distributors in quantities of 1,000 CPUs and not the actual street price of the CPUs. In case you aren’t familiar with the architecture behind Phenom, we’ll provide a very quick overview going over the highlights of the processor.

Phenom is AMD’s first quad-core design, and it’s a native quad-core solution, unlike Intel’s first generation quad-core which is simply two processor dies dropped into one package.

Each of Phenom’s four processing cores has been redesigned to deliver improved performance clock-for-clock over Athlon 64 X2. For instance, the floating point unit supports single-cycle SSE: all 128-bit SSE, SSE2, and SSE3 instructions will complete within one cycle, which effectively doubles the execution speed for these instructions. AMD has also added new extensions to SSE3, while branch prediction has also been improved.

Phenom also boasts a new L3 cache that can be shared across all four cores. The L3 cache size is 2MB. In addition to the L3 cache, each processing core also has its own 64KB L1 cache and 512KB L2 cache (2MB L2 cache and 512K L1 cache total per processor). The memory interface between L1 and L2 caches has also been widened to 256 bits.

To improve performance, the memory controller has been tweaked to take better advantage of the higher memory bandwidth offered by DDR2 memory. Phenom’s new memory controller officially supports DDR2 speeds up to 1066MHz. Phenom also supports HyperTransport 3.0, offering speeds of 3.6GHz full duplex.

With four CPU cores inside Phenom, power is obviously a huge concern. To reduce power consumption, the CPU’s four cores can run their clock speeds and voltages independently of each other: if you’re running a single-threaded app that’s only using one core for example, the other three processing cores can run at lower clocks and voltages to save power. The memory controller can also be powered down to conserve energy.

Phenom is AMD’s first processor to use the new AM2+ socket. AM2+ is fully-backward compatible with AM2 though so those of you with AM2 motherboards should be able to drop in a Phenom CPU when you’re ready to upgrade your existing processor, all you’ll need is a BIOS update. Obviously you won’t get HyperTransport 3.0 speeds though.

Phenom is built on AMD’s 65-nm manufacturing process with SOI, and is manufactured at AMD’s Fab 36 facility in Dresden, Germany. The CPU consists of approximately 450 million transistors and boasts a die size of 285 square millimeters. Both the Phenom 9500 and 9600 share a max TDP of 95W.

AMD 790FX Chipset

Launching alongside the new Phenom processor is AMD’s 790FX chipset. 790FX is designed to appeal to the high-end enthusiast crowd. With up to 42 PCI Express 2.0 lanes, 790FX supports features like triple and quad CrossFire, which can deliver a performance improvement of up to 3X over a single Radeon graphics card, or be used to drive up to eight monitors simultaneously.

HTPC users will love AMD’s new 7-series platform as well. Since it’s built around TSMC’s 65-nm manufacturing process, the chipset consumes very little power. We’ve been told that the chipset boasts a TDP of just 10-12W! That’s less than half the power consumption of high-end chipsets from Intel and NVIDIA, and as a result, the chipset can be cooled by a simple aluminum heatsink. Active cooling isn’t required, even for overclocking. The new chipset also supports AMD’s new Overdrive software.

Up to this point Overdrive has been used solely for GPU overclocking, but with the 790FX chipset, Overdrive can be used to overclock the GPU, memory, and CPU.

AMD provides three basic modes inside Overdrive for overclocking: novice, advanced, and auto overclock. Novice is obviously for beginners and takes much of the guesswork out of the equation for you, overclocking the CPU to certain predefined levels, while the advanced mode lets you tune the system to your heart’s content just as if you were in BIOS, only it’s accomplished via a very robust GUI within Windows. Within the Overdrive interface you can find sliders to adjust voltages, HyperTransport/Memory speeds, the clock multiplier, and a host of other settings. You can also find sections for tweaking memory timings and PCI Express speeds.


Basically all the settings you’d traditionally adjust within BIOS can be found here. AMD even provides a benchmark utility you can use to test the stability of your overclocking endeavors.


Finally, the autoclock feature will automatically try to determine the highest speed that your system can be safely overclocked.


AMD Overdrive also includes hardware monitoring functionality. You can easily monitor temps and voltages of all critical system components within Overdrive, as well as the four processing cores within Phenom itself.

790FX motherboards should be priced in the $150-$250 range, or if Quad-CrossFire isn’t in your future and you want to save a little money on the motherboard, AMD offers their 790X chipset.

The key difference between 790X and 790FX is PCI Express graphics slots – while 790FX supports up to four graphics slots, 790X is limited to two. And while you’re certainly free to take a stab at overclocking with the 790X chipset, motherboards that are built around the platform aren’t tuned as extensively for overclocking as 790FX motherboards are, or at least that’s what we’ve been told by AMD. 790X motherboards should sell for $99-$150.

Finally, for single-card operation AMD offers their 770 chipset. Motherboards based on this chipset are expected to sell between $70-$100.