The Gigabyte GA-M59SLI-S5 is based on Nvidia's high-end nForce 590 SLI chipset, so Gigabyte has sensibly outfitted the board with other high-end features.
For example, each component on the GA-M59SLI-S5 is cooled by a giant heatsink assembly that's linked by three heatpipes. This provides great cooling for the nForce 590 SLI chipset, which in turn should help it to overclock further.
The GA-M59SLI-S5 appears to have three 16x PCI-E slots, but the orange centre slot only has eight PCI-E lanes. If you want to run two graphics cards together in SLI then you have to plug them into the true 16x slots, which are both blue. There are also two PCI slots and two 1x PCI-E slots, although it will be difficult to use one of the latter, as it's so close to the heatpipes linking the Northbridge and VRM heatsinks. The GA-M59SLI-S5 has eight RAID-capable S-ATA II ports, six of which are courtesy of the nForce Southbridge while the other two are provided by a Gigabyte-branded controller. Intel HD Audio is supported, and there are more USB 2 and FireWire ports than you're ever likely to need.
As with most of the nForce 590 SLI-based motherboards in this test, the GA-M59SLI-S5 is a good performer at its stock settings. However, the BIOS only allows you to increase the vcore to 1.55V, although the maximum supported RAM voltage is 2.3V and you can increase the Northbridge voltage by 0.3V. We could overclock the FSB of our test Athlon 64 X2 CPU from 200MHz to 250MHz, which is a smaller overclock than any other nForce 590 SLI motherboard.
When we tried overclocking with the CPU multiplier reduced from 11 to 5, the highest FSB at which the GA-M59SLI-S5 would run stably was 270MHz, which is again disappointing.
Considering its high-spec chipset, the GA-M59SLI-S5 is a disappointing overclocker. Given that it's only slightly cheaper than some of the better-performing nForce 590 SLI boards, we can't recommend it.
Author: James Gorbold
Gigabyte GA-M59SLI-S5