Layout and Features of the P5N32-SLI Deluxe
One topic that we hit on heavily when we evaluated Abit's AW8-MAX, was on the passive cooling methods which collectively were dubbed "Silent-OTES" technology. These methods consisted of a singular heatpipe connected from the Northbridge heatsink to a radiator placed near the I/O ports, specially placed heatsinks near the CPU, and "OC Strips" used to pull heat away from the PCB. Although we had already seen some of Asus' previous attempts at system cooling with the P5WD2, it appears that with the P5N32-SLI Deluxe Asus expands on similar techniques that Abit explored as well.
Rather than simply adding a single heatpipe to cool the chipsets, we've got two of them, one each running from the SPP Northbridge and MCP Southbridge to radiators placed around the CPU. While we appreciate the extra steps at cooling these chipsets (in fact, the SouthBridge still gets quite hot - enough so that we could not keep our finger on the heatsink for more than a few seconds), the placement of the radiators seemed somewhat puzzling. With the AW8-MAX, the radiator was placed at the edge, essentially bumping off legacy connections such as the parallel and serial ports.
With the P5N32-SLI, the radiators are placed in a spot that seems to hinder heat dissipation. One is placed directly behind the IO ports, leaving little room between them and the CPU's heatsink and the other on the edge of the board, which would typically find itself placed right up against the PSU (although a properly place PSU exhaust fan sucking warm air in, could be very benefitial to this setup). This doesn't even take into account that the ATX power connection is placed in the middle of the two radiators, so we'll have cables snaked around here as well. It all adds up to a lack of airflow and increased heat build-up around the CPU, when we should be looking for the opposite.
To Asus' credit, we did receive a shipment a few weeks after we initially started testing the board that included two small fans that could be snapped onto the top of the heatsinks. Alas, these came with a warning that they should only be used in junction with passive or water cooling methods. Using them with a standard setup, the instructions warned, could interfere with CPU cooler airflow and thus should be avoided. A setup that would work perfectly here, in our opinion, would be installing one of the oversized heatsinks, such as those that Zalman markets. At least in this configuration, the large 120mm fan from the CPU cooler could cool down the CPU heatsink and blow air over these mini-heatsinks as well. In fact we've tested this exact setup in the HH labs with the Asus A8N32 SLI, which has a similar cooling configuration and it worked quite well.
In direct contrast to the concerns we had so far concerning CPU cooling issues, the P5N32-SLI utilizes an 8 phase power desgin. The power array around the CPU socket is a neat and tidy design, that builds a steady clean power supply enviroment for the CPU. As such, the board should allow for more stability when operating at standard load as well as providing better overclocking potential. Additionally, as this board is one that can support more than one video card, Asus has placed additional space between the PCI-e x16 slots for improved thermal characteristics. Generally speaking, this allows for greater airflow over the heatsinks for each card, and specifically will allow users to install two of Asus' Extreme N7800GTX TOP graphic cards, or any cards that have dual-slot oversized coolers on them.