AMD Phenom X3 8400 socket: Socket AM2+
The AMD Phenom X3 8400 uses the Socket AM2+ socket. It is a 95 W triple-core Toliman part at 2.1 GHz with 3x512 KB of L2 plus 2 MB of shared L3, from the first triple-core launch.
- Socket
- Socket AM2+
- Launched
- March 2008
- Cores and threads
- 3 and 3
- Default TDP
- 95 W
- Codename
- Toliman
- Segment
- Desktop
- Family
- AMD Phenom X3
- Clocks
- 2.1 GHz
AMD Phenom X3 8400 specifications
| Cores | 3 |
|---|---|
| Threads | 3 |
| Core architecture | Toliman cores on 65 nm |
| Clocks | 2.1 GHz (no turbo) |
| Cache | 3x512 KB L2 plus 2 MB shared L3 |
| Default TDP | 95 W |
| Manufacturing process | 65 nm |
| Memory support | DDR2-800 and DDR2-1066, two channels |
| HyperTransport | 1.8 GHz |
| PCI Express | PCIe Gen 2 from the board chipset |
| Integrated graphics | None (board video where fitted) |
| Multiplier | Locked |
| Package | Socket AM2+ (940 pins) |
| Core voltage | 1.20 to 1.25 V |
Motherboard and chipset compatibility
AMD Phenom X3 8400 needs a motherboard with a Socket AM2+ socket. The table shows which chipset series accept it.
| Series | Chipsets | Support |
|---|---|---|
| 700 series | 790FX, 790X, 770 | Works out of the box |
Board makers publish a CPU support list for every model. Check it for your exact board before buying. Chipset details for Socket AM2+.
Socket AM2+ at a glance
| Type | PGA, 940 contacts |
|---|---|
| Package size | 40 × 40 mm |
| Introduced | November 2007 |
| Memory | DDR2 up to PC2-8500 (DDR2-1066), two channels |
| Cooler mounting holes | 48 × 96 mm |
What the Phenom X3 8400 is
The AMD Phenom X3 8400 is a 2.1 GHz triple core from the first triple-core launch on March 27, 2008. It runs three K10 cores at 2.1 GHz with no turbo, so 3 cores give 3 threads. Cache is 512 KB of L2 per core under a shared 2 MB L3 on a 65 nm process. Power is rated at 95 W on Socket AM2+.
The 8400 is built on the older B2 stepping, part HD8400WCJ3BGD at 1.20 to 1.25 V, which carries the TLB erratum that the later B3 50-series triples fixed. Its HyperTransport link runs at 1.8 GHz. It exists because AMD harvested Agena quad dies with one faulty core into a cheaper triple-core line.
Socket and motherboard compatibility
The 8400 needs a Socket AM2+ board with DDR2 memory and a BIOS that recognizes first-generation Toliman parts. Boards may need the TLB erratum workaround BIOS for B2 steppings. The Socket vs chipset: what decides whether a CPU works guide covers pairing rules.
Memory, PCIe and cooling
Memory is DDR2-800 and DDR2-1066 in two channels.
HyperTransport 3.0 at 1.8 GHz links the CPU to the chipset. PCIe Gen 2 slots hang off the chipset.
Cooling should be rated for 95 W on the 48 x 96 mm mount, with Cool'n'Quiet trimming clocks and voltage at idle.
Upgrade paths
On Socket AM2+ the upgrade is the AMD Phenom X3 8450 at the same 2.1 GHz on the fixed B3 stepping, or the AMD Phenom X3 8750 at 2.4 GHz for full-speed B3 triple-core work. The AMD Phenom X4 9550 adds a fourth core at 95 W where the board allows.
Frequently asked questions
What socket does the Phenom X3 8400 use?
Socket AM2+, the 940-pin package on DDR2 boards with HyperTransport 3.0.
How many cores does the Phenom X3 8400 have?
Three cores and 3 threads at 2.1 GHz with 512 KB of L2 per core plus 2 MB of shared L3.
What is the difference between the Phenom X3 8400 and 8450?
The 8400 is a B2 stepping with the TLB erratum; the 8450 is the same speed on the fixed B3 stepping.
Sources and verification
Facts last checked against these sources on . Page last edited on .