Earlier this month we provided a launch-day preview of the P55 Chipset on Linux along with benchmarks from the Core i5 750 and Core i7 870, which are the new quad-core Lynnfield processors. We noticed some odd performance issues under Linux when testing out these new processors, but Intel has since chimed in and we are in the process of running an updated set of tests.
As yours truly was out of the office last week, there are not new Phoronix-provided numbers to share today, but Intel has submitted their own numbers from the Phoronix Test Suite and provided feedback on the situation. With that said, Intel believes that Turbo Boost is functioning correctly with the newer Core i5 / Core i7 processors on the P55 Chipset and that there were not any unusual variability issues when it was enabled, but this may be a BIOS problem. We will be running our own tests using a newer BIOS for the Intel P55 motherboard shortly. With these Intel-provided results, they are using a newer, shipping BIOS and not an older BIOS provided to the press.
For Intel's Phoronix Test Suite numbers they used an Intel Core i5 CPU clocked at 2.66GHz with a P55 motherboard, 2GB of DDR3 memory, an 80GB INTEL SSDSA2MH08, and a NVIDIA GeForce 9800GTX graphics card. This hardware configuration is almost identical to that of our earlier Lynnfield test system, but with a better solid-state drive. On the software side, their tests came from an Ubuntu 9.10 daily snapshot as well using the Linux 2.6.31 kernel, GNOME 2.27.92, X Server 1.7.3, the NVIDIA 185.18.36 display driver, GCC 4.4.1, and an EXT4 file-system. With this system, they actually ran it in three configurations with the Core i5 750 using the Intel BIOS defaults, the system with Intel BIOS defaults after a reboot and rerunning the tests (for looking at any scores deviating or other variability), with the BIOS defaults but with Compiz enabled, and then they ran the system with no SpeedStep Technology or Turbo enabled.
Intel was running Phoronix Test Suite 2.2.0 Alpha 1 with their tests and was testing directly against the test profiles / options we had used. In fact, thanks to the power of the Phoronix Test Suite, our test results are plotted on the left hand side in the following graphs while the four Intel-provided results are on the right. In this article are the Nexuiz, GraphicsMagick, John The Ripper, LAME MP3 encoding, PostgreSQL, Apache, C-Ray, NAS Parallel Benchmarks, and Stream. Again, these results were provided by Intel, so take them as you will with them being vendor-provided. We are simply sharing these numbers as an update on the situation until we have repeated the tests with a different BIOS.