AMD 780G Motherboards

It has been an agonizingly slow process dissecting seven boards and trying to devise a set of benchmarks that satisfy the home theater, casual gaming, and home office crowds all at once. We think our roundup will come close but there are sure to be a few bumps in the road. We await your comments on the upcoming video analysis and roundup articles over the coming days.

However, we almost did not finish our testing (we actually still have some Phenom benchmarks to complete) as we lost four of our seven boards during final benchmark sessions this past week. It very easily could have been seven out of seven, but we stopped the killing spree after verifying why our boards seemed content to go to digital heaven without Kevorkian assistance. We could stop here and say wait for the article, but that would be sensationalist journalism, right?

Our normal course of testing has us installing a wide variety of processors in each board, regardless of the target market. We do this to ensure compatibility, and at times (like now) we wish this was not the case. This week, we tested the 780G boards with the LE1600, 4400+ X2, 4850e X2, 6400+ X2, Phenom 9600BE, Phenom 9900, and now the 9850BE.

We discovered quickly that running the 9900/9850BE or 6400+ X2 on these products resulted in the loss of the board, in a matter of a few seconds to a few minutes. Granted, it will probably be rare that a user will purchase a 9850BE to run on this platform, but in case you were considering that course of action, we highly suggest you do not. Let’s get this out of the way quickly; it is not a 780G chipset problem.  In fact, it is not strictly a board problem either, but rather a design issue.

This design issue can just as easily occur on NVIDIA or Intel chipset boards, so while we are talking about the 780G product line, just be aware that it can happen on any board with any chipset. In fact, our last GeForce 8200 has already experienced a painful demise. The design issue comes down to the manufacturer trying to balance performance requirements and costs when providing a product in this market sector. The budget sector is very price sensitive, and for the most part users will typically use a lower-end processor.

The vast majority of the 780G boards have a three-phase or four-phase PWM circuitry design. These designs are completely acceptable for the 45W, 65W, 89W, and 95W TDP rated processors; however, drop in a 125W TDP processor such as the Phenom 9850e or 6400+ X2 and you are asking for trouble. Trouble is exactly we found, as each board we tested eventually succumbed to the greater power requirements of these 125W TDP processors.


The four-phase motherboards held out longer and seemed to run fine at stock speeds for a short period. Trying to overclock these boards even slightly resulted in almost immediate board failure. The three-phase boards did not fare as well since we blew MOSFETS on power-up, or they failed after a short OCCT load. We have returned the failed boards for analysis. However, we are comfortable with our statements after spending the past two days on the phone with the board manufacturers and AMD.

Now for the kicker. Although we were testing with a Phenom processor, that does not mean the manufacturer had qualified the board with this particular CPU. So while those front page ads and marketing information list all the processor families that will theoretically run on a board, users need to read the fine print or search for the suppliers' QVL/CPU support lists to ensure the desired processor has been qualified. We also plan to provide this information in the review process.

We searched each vendor’s website to find out if we were “running” the board out of spec with the 9850BE/9900 processors. What we found was very interesting, and we are having spirited discussions with the motherboard companies and AMD at this time.

Index Pop goes the MOSFET
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  • Lashek - Wednesday, April 23, 2008 - link

    Reviewer Product Review

    Manufacturer Response:Those are unusual issues, especially the CPU multiplier adjusting. We do have a new BIOS that has just been released (www.xfxforce.com) also feel free to contact myself at Neweggsupport@xfxforce.com or the XFX Support staff at www.xfxforce.com / 800-880-3225 so we can help out
    SUPPORTWindows Vista32/64 Realtek Audio (R1.90) support files for product MB-N790-IUL9 have recently been updated. (Friday, April 18, 2008)SUPPORTWindows XP32/64 Realtek Audio (R1.90) support files for product MB-N790-IUL9 have recently been updated. (Friday, April 18, 2008)SUPPORT790i SLI Bios Update Nvidia (P04) support files for product MB-N790-IUL9 have recently been updated. (Monday, April 21, 2008)SUPPORT790i SLI Bios Update XFX (P04) support files for product MB-N790-IUL9 have recently been updated. (Monday, April 21, 2008)HELP DESKXFX reply to ALL messages via the ticket system. We send automated emails to advise if we have new information available, due to the nature of email we cannot guarantee delivery of and so recommend that you log in regularly.HELP DESKXFX reply to ALL messages via the ticket system, but Due to unprecedented demand of our support, we are currently experiencing longer waiting times than normal. Please allow upto 48 Hours for an initial response. Alternatively please use our LIVE HELP system, this is available from the drop down box next to your registered product. Thank you for patience, regards XFX SUPPORT TEAM



  • Lashek - Wednesday, April 23, 2008 - link

    Reviewer Product Review
    Lashek Tech Level: somewhat high Ownership: 1 month to 1 year This user purchased this item from Newegg.com 4/15/2008 5:41:49 AM memory problems

    Pros: superior porformace ,and bios menus 4 u overclockers .and easy setup

    Cons: a) CPU multiplier likes to changes at will, causing an inability to POST after changing BIOS options. (Problem is likely linked to bad NVIDIA base code). b) Poor memory read performance above 475FSB unless you enable “P1” and “P2” which NVIDIA refuses to document operation of or provide information about. c) EVGA/XFX (NVIDIA reference design) lacks support for tRFC tuning - high density DDR3 configurations often refuse to work unless the module SPDs are tuned from the manufacturer. (This makes them needlessly slow in low-density configurations.) d) The chipset does not do a very good job of balancing read vs. write priorities with respect to memory access - copy scores lower than X38/X48. e) Regardless of what NVIDIA says, we think PCI-E 2.0 (and 1.x) implementation is still better on Intel’s Express chipsets - give us SLI on Intel to prove it!!! f) Possible problem with NVIDIA reference design: sustained overclocked operation at >~1.9V for VDIMM may cause critical failu

    Other Thoughts: buy asus striker Extreme board instead! Manufacturer Response:Those are unusual issues, especially the CPU multiplier adjusting. We do have a new BIOS that has just been released (www.xfxforce.com) also feel free to contact myself at Neweggsupport@xfxforce.com or the XFX Support staff at www.xfxforce.com / 800-880-3225 so we can help out
  • recneps77 - Friday, April 11, 2008 - link

    So was the Gigabyte stable @ stock?
    Because I learned of all this AFTER my cpu had shipped..
    its a 9750, 125W.
    The board is back ordered, so I can cancel it if need be, but its gonna cost me a 'restocking' fee to exchange the cpu (such a rip).

    Can anyone confirm this for me?
    Gigabyte's site lists all of the B3's under supported, except the 9850 says 'unofficially supported'
  • bobaboo - Sunday, April 13, 2008 - link

    it will run it just fine
  • Visual - Thursday, April 10, 2008 - link

    [quote](4/9/08 Update - We will post an update to this article on 4/10/08 that addresses problems/concerns raised in this story, working with Gigabyte / ASRock on 9850BE certification tonight)[/quote]
    I have been waiting anxiously for the update since yesterday... If I'm not hallucinating this text used to say the update will come on 4/9 and it now says 4/10, and the day is almost over...

    I'm starting to wonder, maybe the update is up somewhere, linked between the 3.14-th and sqrt(-1) page of the article and I just didn't notice it...

    LOL yeah, I know I'm not helping any, and I apologize for being so impatient. Of course, take your time and do things the proper way instead of rushing them.
  • amdmobo - Thursday, April 10, 2008 - link

    Hi, you are not alone. I have been waiting the update since 2 days ago. Yeah, they delayed the date I guess.
  • kzi - Thursday, April 10, 2008 - link

    I'd like to run such a 780g board with two monitors attached to it.
    So I hope you don't forget to look how good the display quality is in such a configuration.
  • insider - Thursday, April 10, 2008 - link

    "check gigabytes website the 9850 is now supported on their cpu list for 780g platform.Bios f3"


    can somebody tell me please whether it's safe to run a Phenom 9850 on this MoBo or not ???
  • Sb1 - Thursday, April 10, 2008 - link

    I appreciate Gary and AnandTech for publishing this article.
    When there are problems I think it's good that they get disclosed. It helps the consumers make more informed decisions and in turn shows manufacturers that they need to address the issue or issues. If they do not then people can take their business elsewhere. Because most people don't have time to read up on multiple forums, even if they are into technology. If they handle it correctly and fess up, it may still p**s you off but you can give them the benifit of the doubt because you know that there are problems in most everything. It's how it is handled that make up peoples real opionions over time of a company.

    I was thinking of purchasing that Gigabyte 780G based motherboard and build it for a friend and possibly for myself once I sell two other PC's. Don't know if he wanted the newest 125w quad cores, but if he did and there were problems I probably would of not bought anything from Gigabyte once I found out on forums that they did not properly update their website for CPU support on this and the 680i based ones I luckily came across in the last few days. Now I am going to look elsewhere. I just bought an Abit IP35 Pro and was seriously considering a Gigabyte board, told my friend to get one for his Q6600 last summer and he did.
  • duron266 - Thursday, April 10, 2008 - link

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