AM2+ processor in AM3+ motherboard

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Chrisco90
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AM2+ processor in AM3+ motherboard

Post by Chrisco90 »

I'm not sure if this is the right place to post this, so my apologies if it isn't.

I have an AMD Phenom II x4 3.0GHz processor @ 125W. I currently have a low-grade motherboard that is hampering my processor.

I was told that "AM2+ boards CAN run AM3 CPU's but you are limited by the TDP of the mobo.The processor you have is actually an early version of the Phenom ii x4.It's TDP is very low which is why it will work with the older AM2+ mobo's.All of the Phenom ii x4 you see today are from a revision to improve performance.But in doing so it required a new socket that could support the 125watt(and 150watt in earlier versions)high performance Black Editions.So to answer your question,yes.As long as it's from the Phenom ii or Athlon ii class it will work on an AM3+ mobo."

Is this true? Would I be able to purchase an AM3+ board with DDR3 Ram and be able to use this processor with it? I'm a bit skeptical after reading some people saying that AM2 is not compatible with AM3 because the processors don't have the DDR3 memory controller.
CoachAub
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Re: AM2+ processor in AM3+ motherboard

Post by CoachAub »

If you have an AM2+ Phenom 2 processor, I believe you cannot run it with DDR3 memory. That was one of the limitations. My old machine, AM2+ Phenom 2 x4-940 runs amazingly close to my current machine when it is overclocked to 3.6ghz. I don't think you see a huge difference when upgrading the memory with these systems. There is some improvement, but my benchmarks are similar when clock speeds are similar on Phenom 2s.

3dmark06 CPU score:
FoxConn A7DA-S mobo am2+ with Phenom II x4-940 OC@ 3.60 with 2GB 1066 Ram=5329
MSI GD-65 mobo am3 with Phenom II x4-970 @3.60 with 4GB 1333 Ram=5374

My other scores improved moreso because I upgraded my graphics.
_______________________________________________________
Rig#1: Intel i5-3570K, MSI-B75MA-P45 mobo, G-Skill Ripjaws DDR3-1600 2x4gb, MSI-7870 2gd5t/oc gpu, Tt TR2-600w psu, Tt Commander Snow ed. Case, Cooler Master Hyper212+ HSF, OCZ Agility3 SSD 120GB, WE Caviar Black 750GB
Rig#2: AMD Phenom 2-970, MSI-890FXA-GD-65 mobo, 6GB Geil DDR3-1333, HIS Radeon HD6870 1GB gpu, Antec Quattro-850 psu, Rosewill Conqueror Case, Zalman CNPS-9500 hsf, 1TB Toshiba Sata3 HD
Polairomis
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Re: AM2+ processor in AM3+ motherboard

Post by Polairomis »

AM2+ versions of the Phenom II (such as the 920 and 940) are not forward compatible with the AM3/AM3+ as they lack a DDR3 memory controller. AM3 versions of the Phenom II are forward compatible with the AM3+ and also backwards compatible with AM2+ sockets as they have both an integrated DDR2 and DDR3 controllers.

This is of course all contingent on BIOS support from the motherboard manufacturer.

Best course of action is usually to check supported CPU list on the vendors website as even some board revisions come into play.
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