A New Die

Instead of just glueing two Athlon II X2 250 "Regor" dies together, the Athlon II X4 is a new design, of course, based on modular parts but nonetheless sufficiently different to warrant a new name, i.e. Propus, the forward foot of the western twin Castor in the Gemini formation with the greek letter eta assigned to it (eta geminorum).

The main difference to the Regor die is the return of the "half-cache" that is, instead of featuring the full 1 MB Level2 chache, Propus only has 512 kB per core. In the grand picture, that still adds up to 2 MB L2 cache per die. With the first series of Athlon-64 CPU, similar designs were in circulation featuring the full cache and the half cache and in terms of performance it did not seem to matter too much, in terms of power consumption, though, the savings of the half-cache were quite substantial.

Propus Die:169 mm² and 300 Million transistors.

The Propus die has a reduced transistor count, primarily courtesy of the smaller L2 cache and the complete absence of the L3 cache and weighs in at 300 Million transistors on a die of 169 mm². Initial offerings are at 2.6 and 2.8 GHz for the Athlon II X4 620 and '630, respectively. Otherwise, there doesn't appear to be anything radically new.

Test Configuration and Power Measurements

We tested the AM3 Athlon II X4 620 and 630 in the following system configuration:

• Motherboard: ASUS M4A79T
• Memory: OCZ3ALVE16004GK
• CPU: AMD Athlon II X4 620 / 630
• Cooler: OCZ Vendetta 2
• Memory: OCZ2RPR10664GK**
• Graphics Card: PowerColor MM RADEON 4890
• HDD: HDD: WD 1500ADFD (Raptor)
• SSD: Intel SSDSA2MH080G15E (80 GB)
• Optical Drive: HP dvd1070i-H01 6 Multiformat DVD writer
• PSU: OCZ EvoStream (720W)

** The memory was run at 1600 MHz 8-8-8

Benchmark Overview

• Microsoft XP-32 Pro / Windows 7 64 (RTM)*
• SiSoft Sandra 2009 SP4
• Adobe Photoshop CS4
• CPU-Z 1.49
• Caligari TrueSpace 5.1
• Caligari TrueSpace 7.5 / VRay 1.51
• Cinebench 9.5
• Cinebench 10
• DIEP Chess
• FarCry2
• Microsoft Excel
• MainConcept H.264
• DVD-Shrink 3.2
• Nero 9 Recode
• VirtualDub 1.76 with DivX 6.8
• Crysis "Demo"
• Devil May Cry 4
• Unreal Tournament3

* We used a fresh install of XP-32 Pro as well as Windows 7 -64-bit (RTM)

For comparison purposes, all benchmarks were run in WinXP 32 unless indicated otherwise.

Power Measurements

Looking at system power consumption is interesting to a certain degree, however, for all practical purposes we are more interested in the isolated CPU power consumption. To estimate the latter, we used the same power measurement setup as in previous reports. Briefly, we used a Fluke 80i-410 AC/DC current probe in combination with a Wavetek Meterman 30XR multimeter to measure current through the isolated +12V supply lines feeding into the CPU VRM. To increase granularity of the measurements, we ran the supply lines in a triple loop through the clamp. The clamp itself was calibrated using a BK Precision model 1692, 30V 40 A DC power supply. Since there is a temperature dependency of the probe, we monitored the zero-current offset at the beginning of each measurement as well as at the end of each run. If the values drifted we retook the measurements. Despite these precautions there are possible deviations of the read-out from the real current, however, these errors mostly affect the lower (processor idle) measurements. We estimate that the errors should not be more than 10% at the lower end of the data and less than 5% in the mid and higher data range. Moreover, since the same procedures were applied to all processors tested, there may be an offset in the absolute numbers, however, the relation of the individual cores to each other with respect to power consumption should be fairly accurate.

Having learned our lessons regarding power measurements on the Nehalem platform, we verified that the 4+1 phases of the VRM receive their power from the 12V auxiliary power plug by ohming out the connections between the MOSFETs and the plug on one side and the MOSFETs and CPU socket on the other side. In theory, showing the electrical continuity does not exclude additional supply power coming in from the 24 pin main eATX connector, however, we also checked there and got "open circuit" readings. This means that we can with reasonable certainty claim that the entire CPU power, including cores and NB/IMC (but excluding I/O power) is derived exclusively from the auxiliary 4-pin 12V input. Details are given on this page.

In addition to the method outlined above, we used a modified PSU to run the 12V line directly through the Wavetek Meterman and read out the current. Both methods gave identical results.