Socket AM3 is a CPU socket for AMD processors. AM3 was launched on February 9, 2009 as the successor to Socket AM2+, alongside the initial grouping of Phenom II processors designed for it.[1] The sole principal change from AM2+ to AM3 is support for DDR3 SDRAM. The fastest CPU for socket AM3 is the Phenom II X6 1100T.
 | |
| Release date | February 2009 |
|---|---|
| Type | PGA-ZIF |
| Chip form factors | PGA |
| Contacts | 941 (Socket) 938 (CPU) |
| FSB protocol | HyperTransport 3.x |
| FSB frequency | 200 MHz System clock HyperTransport up to 2.6 GHz |
| Processors | Phenom II Athlon II Sempron Opteron 1380 Series |
| Predecessor | AM2+ |
| Successor | AM3+ |
This article is part of the CPU socket series | |
Like the previous AMD socket, the "AM3 Processor Functional Data Sheet" (AMD document number 40778) has not been made publicly available. The "Family 10h AMD Phenom™ Processor Product Data Sheet" (document 446878) has,[2] but contains only a brief list of features of the Phenom, and does not contain any substantive technical data regarding socket AM3.
Compatibility
editSocket AM3 breaks compatibility with AM2/AM2+ processors due to a subtle change in key placement. The AM3 socket has 941 pin contacts in a different layout[3] while AM2+ processors have 940 pins. Tom's Hardware removed the two obstructing key pins from an AM2+ Phenom processor in order to fit it into an AM3 socket. The processor did not work in the AM3 socket, but still worked in an AM2+ socket, suggesting that compatibility issues run deeper than merely the key pins.[4] It is likely because the built-in memory controller in AM2/AM2+ processors only supports DDR2 (unlike AM3 processors, which support both DDR2 & DDR3 memory).[5] In fact, a few motherboards were manufactured that supported both DDR2 and DDR3, however only one type could be used at a time. Despite using an AM3 socket and despite using a northbridge and southbridge found on AM3 motherboards, they support any AM2, AM2+, or AM3 processor.[6]
As AM3 processors also support DDR2, they are backwards-compatible with Socket AM2/AM2+, contingent upon a BIOS update for the motherboard. Manufacturers including Asus,[7] Gigabyte,[8] and others have labeled existing AM2/AM2+ boards as being "AM3 Ready" or similar, indicating that BIOS support is provided for the specified boards. This allows existing AM2/AM2+ systems to upgrade the CPU without having to upgrade any other components.
Heatsink
editThe 4 holes for fastening the heatsink to the motherboard are placed in a rectangle with lateral lengths of 48 mm and 96 mm for AMD's sockets Socket AM2, Socket AM2+, Socket AM3, Socket AM3+ and Socket FM2. Cooling solutions should therefore be interchangeable.
Socket AM3+
editAM3+ is a modification of the AM3 socket. It has one additional pin for new Bulldozer-based AM3+ processors and is backwards-compatible with AM3 processors. It broke backwards-compatibility between AM3+ processors and AM2 and AM2+ motherboards because the processors do not support DDR2 memory.
See also
editReferences
edit- ^ The Phenom II X4 810 & X3 720: AMD Gets DDR3 But Doesn't Need It, AnandTech, 2009-02-09, retrieved 2012-01-10
- ^ Phenom II Processor - Product Data Sheet (PDF), Amd.com, retrieved 2012-01-10
- ^ MSI Releases AM3 Gaming Series Motherboards, Hothardware.com, 2009-01-22, retrieved 2012-01-10
- ^ Modding And Overclocking–Doable? : Socket AM3: AMD's Phenom II Gets DDR3, Tomshardware.com, 2009-02-09, retrieved 2012-01-10
- ^ AMD Phenom II - DDR2 vs. DDR3 Performance, Tweaktown.com, 2009-03-11, retrieved 2012-01-10
- ^ MSI Unveils DDR2+DDR3 Combo Motherboard, Tom's Hardware, 2009-03-07, retrieved 2014-12-31
- ^ ASUS Motherboards Now Supports AMD AM3 Processors, Event.asus.com, retrieved 2012-01-10
- ^ "Gigabyte: Products: Motherboard". Gigabyte Technology.
External links
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