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I have a mobo (Asus 870-G45 with AM3), and its running a Phenom II x6 Thuban 1055T, 125W AM3 CPU. I was looking at replacing the CPU with the AMD FX-8120, 125W AM3+ cpu and I couldn't find any info if that would be a compatible replacement. Anyone know if AM3+ can go into AM3 sockets and would this replacement be ok because they have 125W thermal design? Thanks

I'd only do this "upgrade" if there's a killer feature you really want from the FX. The 8120 is a dog...my Phenom II X4 @ 3.5 was faster in anything single or lightly-threaded.

Also - your motherboard doesn't support AM3+ CPUs as far as I know (the latest BIOS update is from 2011).

EDIT: The CPU support list doesn't list any FX CPUs: http://www.msi.com/product/mb/870-G45.h ... CPUSupport


Perhaps contacting MSI (since I assume you meant MSI, not ASUS, based on the model number) is the best course of action if you're really determined to do this "upgrade".

AM3+ in an AM3 board might work, or it might not. It depends on the motherboard and the BIOS. If the BIOS was last updated in 2011 it is a long shot.

Also, I agree with Waco - there's not much point in going from the 1055T to the FX-8120. Pretty much the only good reasons I can think of are A) your workload can fully utilize the extra 2 cores; or B) you need full SSE4 instruction support. If you were looking at jumping all the way to an FX-8350 there might be a point to this, but even then you probably wouldn't notice much of a difference on most real-world applications.

Isn't there an extra pin on the CPU that prevents use in non-AM3+ boards? I thought that's why AM3+ sockets are black.

edit: yes, there's an extra pin.

As we've mentioned, Bulldozer-based CPUs should be compatible AMD's existing socket infrastructure. On the desktop, that's AMD's Socket AM3+ platform, which the company introduced back in May alongside its 9-series chipsets. FX-series processors have 942 pins, one more than older Socket AM3 CPUs, and that pin prevents them from dropping into anything but true Socket AM3+ motherboards. On the flip side, Socket AM3+ boards are capable of hosting older Socket AM3 processors like the Phenom II just fine.

http://techreport.com/review/21813/amd- ... rocessor/4

I wouldn't go to an 8150 at all. No x1xx CPUs should ever be bought. If you want to go AMD get an x3xx CPU. And a new motherboard.

have a look at this page http://www.cpu-upgrade.com/mb-ASUS/index.html scroll down to 870 model have a look at the latest bios updates that are available, but for an FX i think you're SOL.

derFunkenstein wrote:

Isn't there an extra pin on the CPU that prevents use in non-AM3+ boards? I thought that's why AM3+ sockets are black.

edit: yes, there's an extra pin.

Some AM3 boards apparently have the appropriate pin location unblocked, e.g. the Asus Crosshair IV Formula: http://www.asus.com/Motherboards/CROSSH ... A/#support

It does say "beta support only" for the FX CPUs though, so even in this case it is not a fully supported configuration.

ah, ok. I think if it was stable they'd have released a stable BIOS by now

just brew it! wrote:

derFunkenstein wrote:

Isn't there an extra pin on the CPU that prevents use in non-AM3+ boards? I thought that's why AM3+ sockets are black.

edit: yes, there's an extra pin.

Some AM3 boards apparently have the appropriate pin location unblocked, e.g. the Asus Crosshair IV Formula: http://www.asus.com/Motherboards/CROSSH ... A/#support

It does say "beta support only" for the FX CPUs though, so even in this case it is not a fully supported configuration.

I'm currently running an FX-8350 @ 5ghz w/CnQ on this board, CPU dips to 1.4ghz @ idle.

Yeats wrote:

just brew it! wrote:

Some AM3 boards apparently have the appropriate pin location unblocked, e.g. the Asus Crosshair IV Formula: http://www.asus.com/Motherboards/CROSSH ... A/#support

It does say "beta support only" for the FX CPUs though, so even in this case it is not a fully supported configuration.

I'm currently running an FX-8350 @ 5ghz w/CnQ on this board, CPU dips to 1.4ghz @ idle.

That's good to know.

"Beta" doesn't necessarily mean "broken"... it just means "not guaranteed to work". FWIW I'd probably trust an Asus beta BIOS more than I'd trust an official release from some other vendors...

The only issue I've encountered is NB/HT overclocking is nearly nonexistent - I'm stuck at 2300mhz.

I did the Orachi-CEG microcode fix for Steam preemptively, so I don't know if that would have been an issue or not.

I also have an FX-8350 running @ 4.5ghz default voltage in my g/f's MSI 890GXM-G65 and it's been perfect.

Kudos to both Asus and MSI.