nForce4 Ultra Roundup: Charting the Mainstream

Epox 9NPA+ Ultra: Overclocking and Stress Testing

Overclocking

Front Side Bus Overclocking Testbed
Epox 9NPA+
Processor:	Athlon 64 4000+ (2.4GHz, 1MB Cache)
CPU Voltage:	1.55V (default 1.50V)
Cooling:	Thermaltake Silent Boost K8 Heatsink/Fan
Power Supply:	OCZ Power Stream 520W
Memory:	OCZ PC3200 EL Platinum Rev. 2 (Samsung TCCD Memory Chips)
Hard Drive:	Seagate 120GB 7200RPM SATA 8MB Cache
Maximum OC: (Standard Ratio)	240x12 (Auto HT, 2-3-2-7, 1T, 2.9V) 2880MHz (+20%)
Maximum FSB: (Lower Ratio)	302x9 (2718MHz) (Auto HT, 2.5-4-3-7, 2.9V) (1:1 Memory, 1T, 2 DIMMs in DC mode) (+51% Bus Overclock)

The overclocking options finally pay off on the Epox 9NPA+ Ultra, as our Reference 4000+ reached a new stock overclock of 2880MHz (240x12), a 20% overclock of the stock 2.4GHz. The Epox also did well at lower multipliers, reaching a 302x9 speed, which is a 51% overclock of the 200 bus speed. This is still a bit slower than the 318 posted by the DFI, but it placed the Epox in 2nd place for bus speed overclock in this roundup.

Memory Stress Tests

Our memory stress test confirms the ability of the Epox to operate at its officially supported memory frequency (400MHz DDR), at the lowest memory timings that OCZ PC3200 Platinum Rev. 2 modules will support. All DIMMs used for stress testing were 512MB double-sided (or double-bank) memory.

Stable DDR400 Timings - One Dual-Channel (2/4 DIMMs populated)
Clock Speed:	200MHz
CAS Latency:	2.0
RAS to CAS Delay:	2T
RAS Precharge:	7T
Precharge Delay:	2T
Command Rate:	1T

Using two DIMMs in Dual-Channel 128-bit mode, the memory performed in all benchmarks at the fastest 2-2-2-7 timings, at default 2.6V voltage.

Tests with 4 DS DIMMs on an AMD Athlon 64 system are more demanding, since AMD specifies DDR333 for this combination. However, most AMD Athlon 64 motherboards combined with recent AMD processors (the memory controller is on the AMD CPU) have been able to handle 4 DIMMs at DDR400.

Stable DDR400 Timings - 4 DIMMs (4/4 DIMMs populated)
Clock Speed:	200MHz
CAS Latency:	2.0
RAS to CAS Delay:	2T
RAS Precharge:	7T
Precharge Delay:	2T
Command Rate:	2T

Tests with all four DIMM slots populated on the Epox 9NPA+ Ultra board required a 2T Command Rate with 4 DS DIMMs in two dual channels, as we have seen on other top-performing Socket 939 boards, but the memory did operate at DDR400 without any problems. We also checked memory performance with 4 DS DIMMs running a Rev. E AMD processor and found 2T Command Rate was still required with 4 DS DIMMs running with a Rev. E CPU.