The test
For this test, we were able to get our hands on two motherboards. The first was a reference nForce 790i SLI model which is sold by EVGA amongst others. Compared to the nForce 780i SLI motherboard, we can see the addition of a chip that adds management of two supplementary SATA, the first being located next to the first PCI-E port and the second being an eSATA port. Cooling was reviewed and is still heatpipe based. It goes around the Socket and cools the chipset as well as the CPU power blocks and DRAM. The optional fan is the same as that on the 780i and is therefore very noisy although we were assured that it wasn’t the definitive version. Finally, in addition to functions managed by the chipset there is a FireWire chip.
While this is the motherboard that was used in performance tests, we were also able to obtain an ASUSTeK Striker II Extreme at the last minute which we used for evaluating overclocking potential. Based on the nForce 790i Ultra SLI, or the most ‘’overclockable’’ version of the chipset, it is equipped with ‘’Fusion’’ type cooling, in other words, running on passive as well as watercooling.
Specifically destined for those who like to tinker, this motherboard offers amongst other things On/Off buttons and an assortment of LEDs which change from green to red depending on the CPU, memory, and chipset voltage and even the FSB frequency : simply frills ? To each his own. A FireWire chip and two eSATA are also present while the audio component is relegated to a PCI-Express card in order to reduce interference that can affect analog outputs.
For the X38, we used an ASUSTeK P5E3 motherboard.
PCI-Express 2.0
In practice, what does PCI Express 2 support add? This is what we wanted to determine with the help of Crysis, the latest game from Crytek, and which has the most advanced graphic engine at this time. In fact, in standard resolution, 1680*1050, high quality mode causes problems for 256 MB cards and they are required to use central memory to compensate for this.
It’s only in this type of situation that PCI-E 2.0’s supplementary memory bandwidth makes the difference which is something we verified with a GeForce 8800 GT 256 MB:
Tests were run on the first PCI Express port and the third (the second offers the same speeds as the first). With nForces and the X38, the third port is relayed to the southbridge and in PCI-E 1.0 but in x16 and x4, respectively. Here, we should focus on the gain between the nForce 780 and 790i on the first port. Formerly, we were notably behind the X48 but now we are ahead. This is a sign that shaky support of PCI-E 2.0 with the nForce 780 is a thing of the past. In this type of configuration, the last port on the X38 is more decorative than anything else.
With a card equipped with 512 MB of memory such as the Radeon HD 3870, the impact of PCI Express 2.0 is almost nil. Even the scores of the X38’s 4x PCI-E are satisfactory performances are noticeably lower contrary to those of the nForce.
