AMD Phenom X4 9350e - 65W quad-core

AMD Phenom X4 9350e

Manufacturer: AMD
UK Price (as reviewed): Around £115-120 (inc. VAT)
US Price (as reviewed): Around $220 (ex. Tax)

The AMD Phenom has become synonymous with hot CPUs, taking the reins to some degree from the late Intel Prescott (or, Preshot). However, AMD does produce some awesomely energy efficient CPUs that even Intel hasn't matched.

For example, we loved the Athlon 64 X2 BE-2350 in its 45W power envelope, and that was superseded by other BE chips. The efficiency just kept getting better with the Athlon 64 X2 4850e at 2.5GHz, which was also built on the 65nm Brisbane core and was still rated at 45W. This saw the light of day back in February when AMD launched its 780G chipset, though we didn't see stock for a number of weeks after launch.

While AMD's dual-core line has been successful in pursuing its low-power parts, we've only just recently had the launch of the energy efficient quad-core: the Phenom X4 9350e.

Getting the 9350e down to a 65W TDP is an industry-leading move by AMD because, according to Intel, even the Q6600 "energy efficient" G0 core has a 95W TDP. It uses the same 65nm process and K10 architecture that all the Phenoms before it have, and naturally it includes the latest B3 core stepping, although in order to hit the 65W TDP, the core clock has been scaled back somewhat.

The 9350e is clocked at just 2.0GHz with a 1.8GHz northbridge clock. There is also another energy efficient processor with 65W TDP, the 9150e, but that is throttled back even lower at 1.8GHz core and 1.6GHz northbridge.

AMD is targeting system builders with this CPU - combined with the 780G chipset (and also the 790GX which will be available soon), there will be cheap, low-power 'quad-core with Radeon graphics' PCs littering the (virtual) shelves. The benefit of the 65W CPU to system builders is that they can use smaller cases and heatsinks because there's less heat to remove, though the cynic inside us will also point out that the motherboards used can be cheaper, too.

AMD Phenom X4 9350e - 65W quad-core AMD Phenom X4 9350e

AMD claims the 9350e is "perfect for the Home Theatre PC, small form factor PCs and anywhere companies or consumers want a multi-tasking machine that is energy efficient and inexpensive", but exactly how good is it? Does a higher clocked 65W or 45W dual-core offer a better performance than four cores that are clocked lower? From our experience with the Intel Core 2 Duo E8500 (and lower), we found that a faster dual-core is often more beneficial - especially in gaming.

In addition, with integrated GPUs like the 780G offloading video playback from the CPU, we've also shown that for some High-Definition playback you simply no longer need a fast CPU - we played several Blu-ray discs perfectly using very little of even a 45W Athlon 64 BE-2350. But what about other non-GPU accelerated High-Definition playback? After all, not every file type and codec can be handled by the GPU. Does the playback software make use of four low clocked cores, or instead does it need one or two of high clocks instead?

Another question we will answer is how much does Cool'n'Quiet affect performance? AMD is still the only company with a per-core/northbridge PLL to independently clock everything and using it with this lower power CPU is ideal. However, we normally test without C'n'Q turned on to keep a consistent performance base and because when you're overclocking it's best turned off. This time we will test with power saving turned on and off to understand how Cool'n'Quiet can affect the performance (or not) of a low power system.

Finally - how well does it overclock? Since it's a low power processor, surely the silicon is better and therefore there should be more overhead, right? The core voltage is lower too, so there's plenty to play with - we'll see if we've got another "1GHz AXIA/AVIA Thunderbird" on our hands!