Pop goes the MOSFET

Our top performance board in the roundup - thanks to its SidePort memory and optimum layout - is the JW-RS780UVD-AM2+ from J&W. They have a note at the bottom of the product page stating this board does not support 125W TDP processors, and again in the specifications section. We consider this acceptable and for the record, their board failed on power-up with the 9850E. J&W informed us that they will be producing a new five-phase PWM board in an ATX form factor for the performance oriented crowd in May. In the meantime, they have shipped us a new board to complete testing. For a “new” player in the market, we have to admit their customer service and support has been impressive.

The next board up is our all-around feature favorite product from Gigabyte, featuring a four-phase PWM design. The GA-MA78GM-S2H product page does not mention support issues with the 125W TDP processors. It actually states that the board supports the Phenom FX/Phenom processors, leading one to believe all is well. The specification page does not mention any support problems with the 125W TDP Phenoms. It is not until you get to the CPU Support List page that you find out the 9850E has not been qualified on this board, and the same goes for the other quad-core B3 stepping processors. This leaves the user in a quandary as to actual support for the new Phenoms, and hopefully Gigabyte will update the product pages quickly. The board actually runs the B3 stepping fine with the F3E BIOS or higher. However, this board failed after a short overclocking session with the 9900/9850BE processors. It lasted the longest of the boards we tested with either processor and will still power on, but it will no longer POST. Interestingly enough, Gigabyte has qualified the 125W TDP 6400/6000+ X2 processors on this board. We had a new board arrive today and will complete testing on it over the weekend before we subject it to any further overclocking tests with these processors.

We moved to the ASUS M3A78-EMH HDMI board that features a three-phase PWM design. The product page states that the board supports the latest AMD Phenom quad-core processors. Well, guess what: it lasted a mere two seconds with the latest and greatest Phenom processor and about 10 minutes with the 6400+ X2. The specification page is blank so we moved on to the QVL page and found it only contained qualified memory modules. We thought to ourselves, "What would Nancy Drew do?" Low and behold, we went to the download page for the board and off to the left was a box that featured links to CPU Support, Specifications, Product Comparisons, FAQ, and Forum. Sure enough, we clicked on the CPU Support link and found the information we were searching for earlier. Turns out that the Phenom 9100e, 9500, and 9600 are the only qualified Phenom models, and the 125W TDP 6400+ X2 is missing in action as well. This is a long way from the marketing slogan proclaiming support for the latest Phenom quad-core processors.

Next up is the ECS A780GM series of boards that feature ATX and uATX form factors with a three-phase power design. The product and specification pages list AMD Phenom support. Clicking on the CPU support link off to the left brings up one of the more detailed CPU support pages we discovered. However, the 9850BE and 6400+ X2 are both missing. You can guess the outcome by now; while our board is not completely dead, it is on life support and pretty much circling the drain. We were able to shut it down before a complete black out, but the board is no longer stable at any setting.


We stopped testing the 125W TDP processors at this point, although we could have continued with the boards from ASRock, Jetway, and Biostar. Based on their PWM designs, we are sure that each board had a high probability of failure with the 125W TDP processors. In each case, the product pages list support for the full Phenom or X2 processor series and it is not until you go to the CPU support pages that you realize 125W TDP processors are not supported.

AMD also has a very useful tool that provides information about Phenom compatibility across a wide range of motherboards that AMD has tested. None of our test subjects has been formally approved by AMD for use with the 125W TDP processors in the X2 or Phenom product families. We found this interesting as Gigabyte qualified the board for use with the 6400+ X2 but the Athlon X2 compatibility tool does not agree. So who is right? We will find out shortly.

What did we learn? Do not trust the product information and specification pages in the vast majority of cases. The CPU support pages tell the real story - some better than others, but in all cases the 125W TDP processors are not officially supported by current 780G motherboards (4/25/08 update - Finishing 100 hour test results with the 9850BE and three vendor qualified boards have passed to date with proper cooling of the PWM area). It just takes some effort to find that information (except for J&W) and this is something we do not think the user should have to do. In our opinion, the product pages lead the user down one path while the CPU support pages (which are sometimes difficult to find) tell another story. At this point, it pays to read the fine print or hope your favorite review site is able to provide this information.

Personally, I was very disappointed in the type of information available on the websites and in the product manuals. Sure, a manufacturer can hide behind the CPU support lists, but the information provided on the product description and specification pages would lead the majority of users to think using any Phenom or X2 processor is perfectly acceptable when it is not. One would think the manufacturers would be especially sensitive to this problem unless they just enjoy the RMA process and pissed off customers. This especially holds true when purchasing the board from an e-tailor or local shop. Unless the user does some research, the current information available in a product ad or on the box does not tell the rest of the story.

Our stand at this time with the manufacturers is they need to ensure the CPU support page is clearly identified, readily available on the product information page, and it needs to be updated on a regular basis. We also request the CPU support page be linked from the processor support information described in the overview section. If this is not possible then the processor information should be asterisked with a note to check the CPU support page or state what processors are not supported in the short term. Trying to address the channel and retail markets is another can of worms that we will look at later.

We are hoping the short-term fixes occur quickly over the next thirty days; if they do not, well, the product will not be eligible for an Editors' Choice award and you can be certain we will mention processor support in the review. In fact, if a processor is missing from the list we will assume it is not supported and will report it as such from this point forward.

AMD 780G Goes Boom Thoughts about the 790i...
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  • LH2312x - Tuesday, April 8, 2008 - link

    Immediately after reading your news about 780G mainboard problems with 125W TDP CPUs I contacted Asrock about my new A780FullDisplayPort and also asked in Ocworkbench forum about experiences in running a phenom 9850 on an A780FDP.

    Asrock has responded very quickly and their tech support stated that the A780FullDisplayPort mainboard is absolutely capable of running all kinds of 125W TDP AMD chips, including the Phenom 9850! They have implemented a 5-phase PWM on this mobo... phew, thank god I bought this one and not the Gigabyte just laying aside of it :-)

    So, your assumption the Asrock A780FullDisplayPort would have failed also (in case you would have tested it) ist wrong!
  • TrueSport - Tuesday, April 8, 2008 - link

    what a JOKE!
    when the Gigabyte, with high quality components, has to die.
    The crappy Asrock can survive?! LOL LOL LOL
  • TrueSport - Tuesday, April 8, 2008 - link

    just checked out the asrock global site,
    the 9850BE is not listed in the procesor support list, where 9750 and 9650 are there and OK.Also, asking the official Asrock media (ocworkbench), what do you expect to get, NO? no.
    http://www.asrock.com.tw/mb/cpu.cn.asp?Model=A780F...">http://www.asrock.com.tw/mb/cpu.cn.asp?Model=A780F...
  • LH2312x - Tuesday, April 8, 2008 - link

    It's easy. Check the news front page on www.ocworkbench.com. It's there.

  • TrueSport - Tuesday, April 8, 2008 - link

    stop selling your site, it's damn disguisting!
  • LH2312x - Tuesday, April 8, 2008 - link

    First of all, I don't need to "sell a site", since I'm far from being a fan boy like you abviously are? I prefer technical facts, no matter where they are published - as long as I can verify them. Besides that I own mainboards from MSI, Gigabyte, Asrock and Asus. Now THAT is what a call a biased opinion.

    Second, I doubt Asrock would make a public statement like the one being published on OCW if they can't keep up with it. From a product liability stand point this is close to commiting suicide if it is not true - imagine all the people trying to run a phenom 9850 (or any other 125W CPU!) on their A780FDP and frying them...
  • TrueSport - Tuesday, April 8, 2008 - link

    the technical fact is, the asrock board only has 10 mosfets,
    which is less than the Gigabyte's design.
    it can boot into Windows doesn't mean it can run 24hrs a day, 7 days a week in a reliable and stable manner,
    I'm sorry for saying that you are advertising that site, I apologize for that. It's my fault.
  • LH2312x - Tuesday, April 8, 2008 - link

    Simply counting the number of MOSFETs actually doesn't help in determining what current this mainboard can handle (and at which level of stability).
    Just for a quick overview about some basic facts I recommend this from pcper forum:
    http://forums.pcper.com/showpost.php?s=783a95b9912...">http://forums.pcper.com/showpost.php?s=...eeefc5f3...
    OK, enough for theory. Next week I will buy a 9850 and I'll see how it goes!

  • TrueSport - Tuesday, April 8, 2008 - link

    totally agree with you, Prime95/Orthos/OCCT will tell us the answers.
    Looking forward to your tests!
    Regards,
    TS
  • TrueSport - Tuesday, April 8, 2008 - link

    all of us will be glad to see you run a 24hrs OCCT v2 and get a pass with it.
    seriously I will consider to buy one it is capable of doing so.

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