While this is a budget motherboard for ASUS, a Phoenix AwardBIOS is used with a number of settings to help you in overclocking. The P5N-E SLI BIOS supports a CPU vCore voltage up to 1.6V, DDR2 memory up to 2.5V, and the Northbridge up to 1.7V. The motherboard also supports Stepless Frequency Selection, FSB tuning from 200MHz to 750MHz, and PCI Express tuning from 100MHz to 131MHz. The P5N-E SLI BIOS also supports toggling EPP (SLI Ready) memory and Enhanced Intel SpeedStep Technology.
The ASUS P5N-E SLI is our first complete motherboard review under our new motherboard testing approach with both Linux and Solaris. For testing the motherboard's alternative OS compatibility we had used Fedora 7 Test 4, Ubuntu 7.04 Feisty Fawn, KateOS 3.6 Beta, Solaris Express Build 63 "Nevada", and BeleniX 0.5.1. With all of these operating systems, the ASUS P5N-E SLI had functioned as expected without any show-stopping issues like we had seen with the disk controller on the Intel 965-powered Abit AB9 and other motherboards. The only slight issue we had run into was with LM_Sensors 2.10.3, which had properly reported the CPU core voltage, +3.3V, and other motherboard voltages but had not properly shown the sensors for the +5.00 or +12.00 voltage rails. The fan speeds and temperature probes were also reported properly. For Intel Linux users, the NVIDIA nForce 650i and the ASUS P5N-E SLI worked well under Linux during our compatibility tests.
The other hardware we had used when testing the P5N-E SLI was 2GB of OCZ Flex XLC DDR2, an ATI Radeon X1800XT 256MB with the 8.36.5 display drivers, Western Digital 160GB SATA 2.0 hard drive, and an Intel Core 2 Duo E6400 processor. For seeing how well the ASUS P5N-E SLI can perform, we had compared it to the similarly equipped ECS NF650iSLIT-A motherboard (its review will be published at Phoronix tomorrow). During the benchmarking process we had used Ubuntu Feisty Fawn with the Linux 2.6.20 kernel, GCC 4.1.2, and X.Org 7.2.0. Using air-cooling, we also had no problems pushing the E6400 CPU to 3.00GHz with the OCZ memory running at DDR2-1125MHz speeds. This moderate overclock was an ease using the P5N-E SLI.
The benchmarks used for comparing the ASUS P5N-E SLI and ECS NF650iSLIT-A were Enemy Territory, Quake 4, timed disk reads, Gzip compression, LAME compilation, and LAME encoding tests.