P5N-E SLI from ASUS is based on the latest nVidia mainstream chipset for the Intel platform, nForce 650i, being a motherboard targeted to the average user that wants SLI and support for the forthcoming Core 2 Duo CPUs based on the new 1,333 MHz external bus. Let’s take a look on the features and performance of this model from ASUS.

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Figure 1: ASUS P5N-E SLI motherboard.

It is important to know that when under SLI mode nForce 650i makes the two PCI Express x16 slots to run at x8 speed and not at x16. This is exactly the same behavior as other previous mainstream chipsets from nVidia like nForce 570 SLI and nForce 4 SLI. NForce 650i brings two advantages over these two older chipsets. First, it supports the new 1,333 MHz external bus that will be used by new Core 2 Duo CPUs yet to be released; Second, it officially supports DDR2 up to 800 MHz, while these other chipsets supported only up to DDR2-667.

By the way, on the motherboard setup you can configure your memory as DDR2-1066. We did this as we were using DDR2-1066 memories, however the system wouldn’t work correctly, meaning that this chipset really doesn’t support DDR2-1066.

On P5N-E SLI ASUS used a small board to enable SLI mode, just like the very first SLI-based motherboards (see Figure 2). So if you want to use SLI mode you need to remove this board, rotate it, and install it back. In our opinion that is the major flaw with this motherboard, as we think ASUS could have used an automatic switch like everybody else (including themselves) is using on other motherboards.

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Figure 2: SLI selection card.

On nForce 650i chipset the north bridge chip is called C55 and the south bridge chip is called nForce 430i (MCP51) – this is the same south bridge chip used by several other nVidia chipsets. On this motherboard the north bridge chip is cooled down by a passive aluminum heatsink, while no cooling solution was used on the south bridge chip.

On the memory side, ASUS P5N-E has four DDR2-DIMM sockets, supporting up to 8 GB officially up to DDR2-800. On this motherboard sockets 1 and 3 are yellow and sockets 2 and 4 are black. Configuring DDR2 dual channel on this motherboard is pretty easy: just install each module on a socket with the same color.

On the storage side, this motherboard has a total of five SATA-300 ports and two ATA/133 ports – which is a great feature, since it is becoming very hard to see motherboards with more than one parallel ATA port. One of the SATA ports is located on the rear panel of the motherboard, uses an eSATA connector and is controlled by a JMicron JMB360 chip. This port is different, as it is a port multiplier connector, so you can’t use a regular SATA cable on it.

The four SATA ports controlled by the chipset support RAID 0, 1, 0+1, 5 and JBOD.

This motherboard has one Gigabit Ethernet port controlled by the south bridge using one Marvell 88E1116 chip to make the physical layer interface.

Even though this motherboard uses a 7.1 audio codec, Realtek ALC883, it only provides 5.1 audio on its analog outouts, since it only has three audio jacks on its rear panel. This codec provides a low (for today’s standards) signal-to-noise ratio for its inputs – only 85 dB. So it is not advisable to use this motherboard for professional audio capturing and editing (the minimum recommended for this application is 95 dB), unless you install a professional add-on audio card on it. Also the maximum sampling rate for its inputs is of 96 KHz, while its outputs supports up to 192 KHz. The signal-to-noise ratio for its output is of 95 dB.

This board has one coaxial SPDIF output soldered directly on the motherboard, which is great as you can easily connect it to your home theater receiver.