Test Setup -


We utilized a wide variety of memory kits from Corsair, OCZ, Patriot, GSkill, Kingston, and Super Talent to verify memory compatibility on our test boards. Our OS and primary applications were loaded on the Kingston 80GB SSD drive and our games were operated off the WD 300GB VRaptor drive. We did a clean install of the OS and applications for each motherboard.

We chose the ASUS GTX275 video card and Corsair’s 750HX power supply. Yes, a 750W power supply is overkill for our micro-ATX boards, but will be required when we test CF/SLI in future P55 reviews. The difference in power consumption was under 1.5W on average between the 750HX and 520HX power supply.

Our air cooler of choice is Thermalright’s Ultra 120 eXtreme, primarily for its exceptional performance during our overclocking tests. We also tested with the retail cooler and those results along with direct CPU comparisons can be found here.

We are providing initial test results with Foxconn’s P55MX. Our test sample had an early revision P55 chipset and the retail board just arrived. Our application and game benchmarks are with the retail board. The board is limited to 4GB of memory in our tests due to the dual slot design.  Our multitask test had two applications removed to bring the memory required footprint down to 3.82GB.  An article update will be generated once we complete our overclocking and stability tests. This board sells for around $90 and is really designed for the business or SOHO user.

Our 790FX/X58 results are provided for comparison only. For our test results we setup each board as closely as possible in regards to memory timings. Otherwise all other settings are left on auto. The P55 and 790FX motherboards utilized 8GB of DDR3, while the X58 platform contained 6GB. The P55 and X58 DDR3 timings were set to 7-7-7-20 1T at DDR3-1600 for the i7/920, i7/870, and i7/860 processors at both stock and overclocked CPU settings.

We used DDR3-1333 6-6-6-18 1T timings for the i5/750 stock setup as DDR3-1600 is not natively supported in current BIOS releases for this processor at a stock Bclk setting of 133. We had early BIOS releases that offered the native 1600 setting but stability was a serious problem and support was pulled for the time being. Performance is essentially the same between the two settings.

The AMD 790FX setup is slightly different as trying to run DDR3-1600 at CAS 7 timings on the 1:4 divider is extremely difficult. DDR3-1600 is not natively supported on the Phenom II series so this divider is provided with a caveat that you are overclocking the memory bus. The same holds true for the Lynnfield (i7/8xx, i5/7xx) processors as DDR3-1333 is officially the highest memory speed supported and it is DDR3-1066 for the Bloomfield (i7/9xx).

Without resorting to some serious overvolting and relaxing of sub-timings, we set our AMD board up at DDR3-1600 8-8-8-20 1T timings. The difference in performance between C7 and C8 DDR3-1600 is practically immeasurable in applications and games on this platform. You might pick up an additional few tenths of second in SuperPi or a couple of extra points in AquaMark or 3DMark 2001SE, but otherwise performance is about equal.

However, in order to satisfy some of our more enthusiastic AMD supporters, we also increased our Northbridge speed from 2000MHz to 2200MHz to equalize, if not improve, our memory performance on the AMD system. Yes, we know, further increasing the NB speed will certainly result in additional performance but the focus of this short article is to show clock for clock results at like settings. Personally, I would run DDR3-1333 C6 with 8GB as this platform favors tighter timings over pure bandwidth.

We will provide P45/Q9550 platform results in the next roundup.

I know what you did last BIOS release...



One problem we constantly ran across in early testing and major reason why we delayed the start of these roundups was the floating Bclk problem. Motherboard suppliers have tweaked FSB speeds for years in an attempt to squeeze out that last little bit of performance at stock speeds. Well, the same thought process went into a few of the P55 BIOS releases from several manufacturers.

Even though we manually set the Bclk rates to 133, a few of the boards decided to still float the Bclk rates up to 138 in some cases, 136 in others. If the manufacturer did not change their BIOS to lock Bclk rates at 133 when manually set to 133, then we set the boards to 132. That in its self caused a few quick BIOS updates and except for one upcoming board, we are no longer experiencing this problem.

ASRock P55M Pro Overclocking Performance Results / Power Consumption
Comments Locked

55 Comments

View All Comments

  • Gary Key - Monday, October 5, 2009 - link

    The PCIe lanes coming off the P55 are 2.0, the problem is that they are running at 1.x speeds (2.5GT/s). On these two boards, the x16 slot is off Lynnfield and will not be affected by any card placed in the x4 or x1 slots off the P55.
  • Mr Perfect - Tuesday, October 6, 2009 - link

    I should probably know this, but what does a 2.0 slot running at 1.x speed bring to the table that a 1.x slot doesn't? Does it provide more power or something?
  • MadMan007 - Tuesday, October 6, 2009 - link

    Yes I was half right with my post and nothing Gary said was technically wrong it's just misleading. They are PCIe 2.0 spec slots but running at half speed, this is clear from Intel's chipset disgram. It's really a farce to call them PCIe 2.0 though because the overridingly most important change from 1.x to 2.0 is the double bandwidth, there are other changes like the power rating I believe and maybe some low level changes but nothing major. I think it's false advertising to call them PCIe 2.0 personally because they don't fully conform to the spec.

    In any case I'd still like to know how many lanes the main CPU-based slot retains when a 1x or 4x card is placed in a secondary CPU-based PCIe slot. Anandtech seems to be more receptive to odd little investigations like this so I hope Gary will check it out.
  • james.taylor - Monday, May 10, 2010 - link

    Hi Gary, Thank you so much for this information
  • james.taylor - Monday, May 10, 2010 - link

    again thanks but if you want to buy new memory then http://www.memoryx.net/ this can help you

Log in

Don't have an account? Sign up now