Sempron 140

As mentioned earlier, the Sempron family is based on AMD's current K10.5 architecture which is also used in Athlon II and Phenom II processors. You may use the Sempron on motherboards with AM2+ sockets and DDR2 memory as well as on the new AM3 socket in combination with DDR3 memory. Its integrated memory controller supports DDR2 up to 800 MHz and DDR3 memory type up to 1066 MHz speeds. Currently there is only one SKU available and that's the Sempron 140, which we are reviewing today.

Sempron 140 comes clocked at 2.70 GHz at 1.35 V operating voltage. It's based on the Sargas core which is equipped with 128 KB L1 cache and 1 MB of L2 cache memory, the total core die size measures 117 mm². Maximum power consumption is rated to a low 45 W, and the possibly best feature of this processor is its price, at just $39. Originally AMD intended these processors to be used in combination with the low-end AMD 760G chipset, which would make a perfect platform for small, efficient, and cheap systems used for web surfing, non HD multimedia playback, or simple office tasks. Low-end AMD motherboards with 760G chipset cost about $55, add to that 2 GB of DDR2 memory, a small case and power supply for another ~$90 and you get yourself a fully functional PC capable of performing every day basic tasks for a total of ~$180.

As it turns out, Sempron 140 is capable of much more than just basic stuff. Running it in a small office desktop computer, you could be very well be wasting a whole lot of potential. If you go with AMD's 780/785G chipset instead of the low end 760G you can have a really solid platform for a home HTPC system. Really silent, really cheap, and efficient; capable of running 1080p HD video with no problems at all. This will be made possible by the integrated HD video decode in the HD 3x00/4200 IGPs.

If you have read the Athlon II X2 240 review, which we recently published, we talked about three native core designs that AMD is using to produce all of Athlon II and Phenom II models. Now you are probably wondering where the Sargas core that is used to power Sempron comes from? You also might have noticed the 1 MB L2 cache memory, similar to new Athlon II X2 models, and after doing some 2+2 math… yup, Sargas is actually the Regor core used in Athlon II X2 with one logic core disabled. And that of course means that with some help from the SB710/SB750 Southbridge and its ACC technology support, you have very high chances for unlocking the second core.

There are several possible reasons for just one Sempron SKU for now. Market demand is turning to cheap dual core CPUs instead of slightly cheaper single cores. The second reason, and this is just my guess, is the very good yields for the Regor core. Statistically speaking, the smaller the core, the better the yields in production, and it really doesn't get much smaller than Regor at 117 mm². So if the yields are good, and let's presume they are, for Regor core, there is no reason to lock away one functional core and earn less money than you would if you could sell it as cheap Athlon II X2. Thus, AMD uses a smaller number of Regor cores which can't operate on certain frequencies required to be branded as Athlon II X2, or if the L2 cache is faulty, one logic core is locked and sent to market as Sargas single core or Sempron 140 if you like. We have seen a large number of successfully unlocked Sempron 140s, which seems to confirm the Regor high yields theory. To meet the demand AMD is just locking away cores on perfectly functional Regor cores, and if you are thinking of buying the new Sempron, be sure to pair it with motherboards that have the AMD SB710/SB750 southbridge chips, which can enable the second core. Our tested processor was successfully unlocked which will be shown in more detail later.



Because Sempron is in fact based on the Regor core, the supported technology and instruction list is the same as with Athlon II X2, which supports everything other Athlon II or Phenom II models support. Even AMD-V virtualization technology is supported, but the single core could end up being too weak for any serious virtualization tasks. Among other supported technologies are support for MMX, SSE2, SSE3, SSE4A instructions, Enhanced 3DNow!, NX bit, AMD64, and Cool'n'Quiet.
Sempron 140 has its frequency multiplier locked to x13.5 and can only be lowered. Overclocking can be achieved by raising the default HT Link value.

Specifications

In the table below you can review detailed specifications of Sempron 140 and other models that will show up later in the performance graphs. Intel's competition in this market segment comes in form of the Celeron 430 which has a single core too.