In practiceFor this test, we were able to get our hands on an EVGA nForce 780i SLI motherboard based on NVIDIA’s reference design, which by the way is very close to that of the nForce 680i SLI. In addition to capabilities inherent to NVIDIA chipsets, there is also the presence of an HD Audio Realtek ALC888S codec and a FireWire Texas Instruments TSB43AB22A controller. On the other hand, the motherboard does not offer an eSATA port. We can see there are both power and reset buttons directly on the motherboard, something very practical for those who like to play with settings and conduct tests outside of the tower casing.
Cooling is assured by a heatpipe based system which relays the MCP, SPP and CPU power stage. It is normally entirely passive but in the case of overclocking an optional fan is included that can be clipped on the main SPP radiator. Unfortunately, it’s quite noisy.
Contrary to what happened with the nForce 680i SLI, the Core 2 Extreme QX9650 functioned perfectly here. On the other hand, the QX9770 did not boot. This is nothing too dramatic given that this CPU isn’t even available yet; however, we can hope the opposite will happen via a bios update even if the FSB1600 is not officially supported by the nForce 7.
In order to evaluate the new chipset, we compared it to the X38 by using an ASUSTeK P5E motherboard whose particularity is to combine the X38 and DDR2. Initially we were going to integrate the nForce 680i SLI for comparison but unfortunately our test board gave out in the middle of tests. Anyhow, the first results showed equivalent performances to the nForce 780i SLI in terms of memory, RAID and network.
PCI Express 2
In practice, what does PCI Express 2 add to the nForce 7?
To answer this question, we used four PCI-E 2.0 video cards, one after the other, on the first and third PCI Express x16 port as they are in versions 2 and 1, respectively. These were two Radeon HD 3870s and two GeForce 8800 GTs, one a 256, the other a 512 MB.
For tests, after the use of various programs we chose 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’s supplementary memory bandwidth makes the difference.
As you can see, 256 MB cards really tire out quickly. Also, the fact that they are on the PCI-E 2.0 port doesn’t radically change the situation because gains are 15% for NVIDIA and 6% for ATI. In their 512 MB versions, the 8800 GT largely surpasses the HD 3870 while this was the opposite case for the 256 MB cards.
Is this related to the nForce 780i SLI’s rather particular management of PCI-E 2.0?
Without a doubt we can say, yes, given the X38’s performances with 256 MB cards. The gain is ‘’only’’ 5.6% for ATI but for the 8800 GT it attains 21%.