AMD Phenom EEs/Overclocking

On the opposite end of the spectrum from the 140W Phenom 9950 Black Edition are AMD’s new Energy Efficient line of Phenom CPUs, the Phenom 9350e and 9150e. These CPUs boast a TDP of just 65W, making them the most energy efficient quad-core CPUs on the market today (in comparison, Intel’s most efficient 45-nm quad-core CPUs feature a TDP as low as 95W). Up to now, AMD had previously only offered one EE CPU, the Phenom 9100e, and AMD was selling it solely to OEMs, excluding the retail market entirely. By now offering these CPUs at retail, DIY’ers can purchase these chips at Fry’s, Newegg, or other retailers and drop them into custom built home theater PCs.

AMD has offered 65W dual-core X2 CPUs at speeds as high as 2.6GHz for some time now, and just added 2.9GHz 65W X2 parts to their lineup for under $100 as well, but if you’re someone who needs more than just two cores for video encoding, heavy multitasking, etc, and you’ve been wanting to build a small form factor or HTPC, these chips are intended for you.

Unfortunately, AMD doesn’t appear to be binning these CPUs, instead their TDPs are obtained solely by running these chips at lower clock speeds and voltages than previous Phenom processors. The Phenom 9150e for instance runs at 1.8GHz, with its memory controller topping out at 1.6GHz. With the HyperTransport interface running at the same 1.6GHz clock speed as the memory controller, this limits peak CPU bandwidth to 29.9GB/sec.

The Phenom 9350e runs at a core clock of 2.0GHz, with a 1.8GHz memory controller bringing peak bandwidth up to 31.5GB/sec. In comparison, other Phenom CPUs top out at 33.1GB/sec.

The nominal voltage of both processors ranges from 1.05-1.15V of juice.

Since they don’t appear to be specially sorted to consume less voltage than other Phenoms however, you could accomplish this yourself by simply undervolting a Phenom 9550 or 9650 CPU and save some money in the process: officially the Phenom 9550 is $20 cheaper than the Phenom 9350e if you go by AMD’s latest CPU list prices.

Overclocking

Unfortunately, our overclocking endeavors with these CPUs were mixed. While we achieved a nice 400MHz+ OC from our Phenom 9950 Black Edition sample, the 9350e topped out at just 2.23GHz at 1.2875V. Increasing the voltage beyond 1.3V didn’t improve stability within Windows, so we’re pretty confident we hit the ceiling of this particular CPU sample.

The max OC we were able to achieve with the Phenom 9950 was 3.055GHz (13.0x235MHz).Despite our best efforts, we couldn’t get the CPU to run with stability any higher