More than just a relic of AMD’s original Spider platform, the 790FX remains the company's only real enthusiast northbridge. The newer SB750 southbridge offers modern peripheral performance too, while DDR3 support via AMD’s latest on-die memory controller is the latest performance trend.
The big reason you'd choose a 790FX over the more “modern” 790GX is its 38 PCI Express (PCIe) 2.0 pathways, which can be configured as two x16, four x8, or a mix of single x16 and two x8 sets, with six pathways to spare. As with the 790GX, AMD’s third-generation HyperTransport interconnect links the 790FX to the AM3 processor, so the only two things more “modern” about the 790GX are its onboard Radeon HD 3300-series graphics core, which enthusiasts don’t want anyway, and its release date.
We have to suspect that most AMD enthusiasts haven’t considered shifting over to AM3 yet because of the lack of top-range clock speeds for DDR3-supporting processors (plus the fact that half are triple-core models, while the other half are quad-cores with cut-back cache).
AMD will release updated models soon, but we can’t give you the speed or the date (Ed.: Here's a hint: check back tomorrow). Until then, many are choosing the Phenom II X3 720 Black Edition for its excellent reputation in overclocking, since most programs can’t take advantage of all four cores of the slower-clocked Phenom II X4 910.
| Socket AM3 Processors | |||||
|---|---|---|---|---|---|
| Model | Frequency | L3 Cache | Voltage | Model # | Socket |
| Phenom II X4 910 | 2.6 GHz | 6 MB | 0.875-1.425V | Tray: HDX910WFK4DGI | AM3, AM2+, AM2 |
| Phenom II X4 810 | 2.6 GHz | 4 MB | 0.875-1.425V | Tray: HDX810WFK4FGI; PIB: HDX810WFGIBOX | AM3, AM2+, AM2 |
| Phenom II X4 805 | 2.5 GHz | 4 MB | 0.875-1.425V | Tray: HDX805WFK4FGI | AM3, AM2+, AM2 |
| Phenom II X3 720 BE | 2.8 GHz | 6 MB | 0.850-1.425V | Tray: HDZ720WFK3DGI; PIB: HDZ720WFGIBOX | AM3, AM2+, AM2 |
| Phenom II X3 710 | 2.6 GHz | 6 MB | 0.875-1.425V | Tray: HDX710WFK3DGI; PIB: HDX710WFGIBOX | AM3, AM2+, AM2 |
- 790FX Is Still The King
- Socket AM3 Motherboard Features Comparison
- Asus M4A79T Deluxe
- DFI LANParty DK 790FXB-M3H5
- Gigabyte GA-MA790FXT-UD5P
- MSI 790FX-GD70
- Test Settings
- Benchmark Results: 3D Games
- Benchmark Results: A/V Encoding And Productivity
- Benchmark Results: Synthetic
- Overclocking, Power, And Heat
- Conclusion

We have no layout complaints, but builders should be aware that all four of the MA790FX-UD5P's add-in SATA ports (white) share a single PCIe pathway through the JMicron JMB363 controller, for a maximum combined throughput of 250 MB/s. That’s far short of the 1,200 MB/s combined bandwidth that four 3.0 Gb/s ports are theoretically capable of supporting.
is a bit scary, but in fact it's not a problem IMO. Even if you happen to copy a huge file from HDD 7 to HDD 8 (both on the JMicron controller), you still get over 100 MB/s bandwidth for each, and that's pretty much the average read/write rate of the WD Caviar Black 1TB. That is, there's no bottleneck after all.