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Asus Sabertooth 990FX Review

Manufacturer: Asus
UK price (as reviewed): £126.54 (inc VAT)
US price (as reviewed): $189.99 (ex tax)

The Sabertooth 990FX was a logical inclusion in our first post-AMD FX motherboard roundup; it earned an Approved award when we first pitched it against other high-end Socket AM3+ motherboards. Apart from a new EFI to provide compatibility with AMD’s new CPUs, however, not a lot has changed. It has the same great layout – similar to that of the Crosshair V Formula - but the PCB is far less busy.

There are six fan headers, two of which are 4-pin PWM-compatible to cater for dual-fan CPU coolers. There are also four PCI-E slots, the lowest of which has just four lanes.

Installing graphics cards in the top two slots means that each has access to the full 16 PCI-E lanes, whereas if the top three slots are all occupied, the second and third slots are limited to eight lanes each. The Sabertooth supports both SLI and CrossFireX. Four USB 3 ports are included – two via the I/O panel, in addition to a USB 3 header on the PCB – and there are ten USB 2 ports.

At stock speeds, the Sabertooth returned much the same results as the other boards on test, with an overall Media Benchmarks score of 1,527 and a minimum frame rate in Arma II of 60fps. Meanwhile, delving into the EFI was the usual slick and trouble-free experience we’ve come to expect from Asus’ motherboards.

In addition, we didn’t have nearly as much trouble with the Sabertooth when it came to overclocking as we did with MSI and ASRock’s offerings – the Sabertooth seemed to accept our tweaking with a minimum of fuss.

We managed a maximum HTT of 350MHz – the same we’ve seen with any other AMD CPU installed. However, when ramping up our FX-8150 CPU’s multiplier, we had to drop the HTT to 270MHz to ensure that it was stable enough to run our benchmarks.

Using a CPU multiplier of 17x, this resulted in a CPU frequency of just below 4.6GHz. We achieved this using voltages set to 1.436V for the vcore, 1.256V for the CPU/NB, 1.225V for the NB 1.31V for the SB. This resulted in a marked improvement in the benchmarks, with the overall Media Benchmarks score rising over 200 points to 1,759 and the minimum frame rate in Arma II seeing a 6fps boost at 66fps.

Conclusion

We had our doubts that any of the black-socket motherboards would offer a hassle-free experience when we dropped in a new AMD FX CPU; while our concerns were correct with the ASRock board and to some extent the MSI, Asus’ Sabertooth board exhibited no such wobbles. The EFI update was straightforward, and overclocking was performed in much the same way as it is with a Phenom II CPU. It’s therefore a shame that Asus has kept its part of the bargain, while AMD has failed to do so.

Specifications

• Chipset AMD 990FX
  
• CPU support Socket AM3 Athlon II, Phenom II Sempron 100-series, Future Socket AM3+ CPUs
  
• Memory support 4 slots: max 32GB DDR3
  
• Expansion slots four 16x PCI-E 2.0 slots (two 16x or one 16x, three 8x and two 4x), one 1x PCI-E, two PCI
  
• Sound 8-channel HD Audio via Realtek ALC889
  
• Networking Realtek RTL8111E Gigabit Ethernet
  
• Overclocking HTT frequency 100– 600MHz; max voltages, CPU 2.1V, CPU NB 1.875V, Chipset 1.5V, HT 1.513V, RAM 2.5V
  
• Ports 2 x SATA 3Gbps, 6 x SATA 6Gbps, 1 x PS/2, 10 x USB 2, 4 x USB 3, 2 x FireWire, LAN, 4 x surround audio out, line in, mic, optical S/PDIF out, eSATA 3Gbps,
  
• Dimensions (mm) 305 x 244 (ATX)