AM2+ CPU in a AM2 motherboard, system bus speed downgrade

mikepegg

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Jun 18, 2008
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Hi Guys,

Considering putting a AMD Phenom II X3 720 Black Edition in a GA-M56S-S3 and although they are compatible on the Gigabyte website it has this note:

*Note: If you install AMD AM2+ CPU on AM2 motherbord, the system bus speed will downgrade from HT3.0(5200MHz) to HT1.0(2000 MT/s) spec; however, the frequency of AM2+ CPU will not be impacted. Please refer "CPU Support List" for more information.

Does anyone know what (if any) impact this will have on the overall speed of the system? And if it will for a gaming machine better to spend the extra £65 on an AM3 board?


Mobo link: http://www.gigabyte.com.tw/Products/...ProductID=2607

Cheers.
 

stridervm

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Jan 28, 2008
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Don't worry about it unless you're gonna run a server which is on load 24/7.

As the HT Speed isn't as important in games. At best it would be a 2% performance decrease. As non existant as using Single channel VS dual channel mode.
 
The downgraded buss speed on the AM2+ boards is not noticable.

A question I have for you, why are picking boards with an nVidia chipset on them?
The boards you have picked do not support SLI, so there is absolutely no reason to buy one with an inferior nVidia chipset. If you are only running 1 video card, you want a board with an AMD chipset on it, even if your GPU is nVidia.

I am running a Phenom II 920 on a MA78GM-US2H, and a 8800GTS 512 OC video card. It scores just over 15,000 in 3D Mark 06. That is not too shabby for an $80 motherboard and old 8800 video card.
 
It's one of the last things that affects gaming performance. While you can raise the HT speed by overclocking the FSB (which really isn't an FSB on AMD CPUs but a base clock), it's usually not advisable on older AM2 boards. If you do so anyway it's best to have an actively cooled north bridge. Anyway I wouldn't worry about it too much ^_^. It's recommended that you set your HT link to 1.0 anyway when overclocking Phenom IIs.
 

zm15

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Apr 7, 2009
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Will a downgrade of this nature affect video editing performance?? I do mainly After Effects editing and rendering. Will the hyper transport downgrade slow things down much? Thanks!!

Zach