For our next round of synthetic benchmarks, we ran the CPU and Memory performance modules built into Futuremark's PCMark05. We incorporated PCMark05 into our benchmark suite soon after its release, and have found it to be even more robust in terms of test features than its predecessor. That said, the CPU and Memory test modules we use for comparison are very similar to the 04 version of the test suite. For those interested in more than just the graphs, we've got a couple of quotes directly from Futuremark that explain exactly what these tests do, and how they work.
"The CPU test suite is a collection of tests that are run to isolate the performance of the CPU. The CPU Test Suite also includes multithreading: two of the test scenarios are run multithreaded; the other including two simultaneous tests and the other running four tests simultaneously. The remaining six tests are run single threaded. Operations include, File Compression/Decompression, Encryption/Decryption, Image Decompression, and Audio Compression" - Courtesy FutureMark Corp.
The Dell XPS 710 H2C easily took the pole position, beating out our custom quad-core rig. This isn't too surprising since the XPS 710 H2C's processor comes factory overclocked to 3.2GHz while our quad-core system was running bone stock at 2.66GHz. Of particular interest in this, and several of our other benchmarks, is the difference in performance between the two test rigs running X6800's. Both systems have been configured identically, except for the motherboard. One is using a motherboard powered by the nForce 590 SLI chipset, the same one used in the XPS, while the second system is using the much newer nForce 680i SLI chipset. As we can see here, the newer chipset does make a difference.
"The Memory test suite is a collection of tests that isolate the performance of the memory subsystem. The memory subsystem consists of various devices on the PC. This includes the main memory, the CPU internal cache (known as the L1 cache) and the external cache (known as the L2 cache). As it is difficult to find applications that only stress the memory, we explicitly developed a set of tests geared for this purpose. The tests are written in C++ and assembly. They include: Reading data blocks from memory, Writing data blocks to memory performing copy operations on data blocks, random access to data items and latency testing." - Courtesy FutureMark Corp.
Here we see some very different results. The XPS' use of the lower speed/higher latency memory results in a memory bandwidth disadvantage, which takes a slight toll in the PCMark05 memory test. Here, our X6800 test rig utilizing the new nForce 680i SLI chipset takes the lead while the XPS finds itself in second place. Certainly, CPU cache and core speeds have affected scores here as well. However, PCMark05 is largely a synthetic benchmark, so we encourage you to look more closely at the read-world application testing that we'll provide next.