Asus P4S800D-E Deluxe & Gigabyte 8S655TX Ultra: SiS 655TX Challenges Intel's Best

Asus P4S800D-E: Stress Testing

We performed stress tests on the P4S800D-E in these areas and configurations:

1. Chipset and motherboard stress testing, conducted by running the FSB at 264MHz with synchronous (1:1) memory speed (DDR528) with OCZ 4200 EL memory.
2. Memory stress testing, conducted by running RAM at 400MHz with 2 Dual-Channel (1 bank) DIMM slots filled and at 400MHz with all 4 Dual-Channel (2 bank) DIMM slots filled at the lowest memory timings possible with Mushkin PC3500 Level II memory.

Front Side Bus Stress Test Results:

We ran a full range of stress tests and benchmarks to ensure that the Asus P4S800D-E was absolutely stable at each of the overclocked FSB speeds. This included Prime95 torture tests, and the addition of other tasks — data compression, various DX8 and DX9 games, and apps like Word and Excel — while Prime95 was running in the background. At default voltage, 267MHz was the highest overclock that we were able to achieve with an asynchronous memory setting; 264 was the highest overclock that we could achieve with a synchronous memory setting.

Memory Stress Test Results:

This memory stress test is very basic, as it simply tests the ability of the P4S800D-E to operate at its officially supported memory frequency (400MHz DDR) at the lowest supported memory timings that our Mushkin High Performance ECC Registered Modules will support:

Stable DDR400 Timings — 2 DIMMs 2/4 DIMMs populated — 1 DC bank
Clock Speed:	200MHz
Timing Mode:	128-bit DC
CAS Latency:	2.0
Bank Interleave:	N/A
RAS to CAS Delay:	2T
RAS Precharge:	6T
Precharge Delay:	2T
Command Rate:	Auto

We had no problem running 2 DS 512MB DIMMs of our standard Mushkin PC3500 Level2 and OCZ 3500 Platinum Ltd in the P4S800D-E at the most aggressive timings. To achieve complete stability at 2-2-2-6 timings, we did have to slightly increase vDIMM voltage to 2.65V.

Filling all available memory banks is more strenuous on the memory subsystem than testing 2 DIMMs, but we had no problem at all running with all 4 DIMMs filled providing 2 Dual-Channel Banks.

Stable DDR400 Timings — 4 DIMMs 4/4 DIMMs populated — 2 DC bank
Clock Speed:	200MHz
Timing Mode:	128-bit DC
CAS Latency:	2.0
Bank Interleave:	N/A
RAS to CAS Delay:	2T
RAS Precharge:	6T
Precharge Delay:	2T
Command Rate:	Auto

The required memory timings with 4 DIMMs were the same as 2 DIMMs, the fastest 2-2-2-6 timings our memory could achieve. For maximum stability, we had to increase vDIMM to 2.65V, the same as our 2 DIMM setup. The P4S800D-E was completely stable at these timings and voltage.

As a side note, at default 2.5 vDIMM, the fastest stable memory timings with both 2 and 4 DIMMs were 2-2-3-6. While most tests were fine at 2-2-2-6, long-term stress testing eventually caused memory failures unless the settings were slowed to 2-2-3-6 or memory voltage was increased to 2.65V. Prime95 torture tests were successfully run at the timings listed in the above charts. We also ran Sciencemark (memory tests only) and Super Pi. None of the three stress tests created any stability problems for the Asus P4S800D-E at these memory timings and 2.65V.