nForce4 Ultra Roundup: Charting the Mainstream

Biostar NF4UL-A9: Overclocking and Stress Testing

FSB Overclocking Results

Front Side Bus Overclocking Testbed
Biostar NF4UL-A9
Processor:	Athlon 64 4000+ (2.4GHz, 1MB Cache)
CPU Voltage:	1.50V (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)	223x12 (Auto HT, 2-3-2-7, 1T, 2.7V) 2677MHz (+11.5%)
Maximum FSB: (Lower Ratio)	232x11 (2552MHz) (Auto HT, 2.5-3-3-7, 2.7) (1:1 Memory, 1T, 2 DIMMs in DC mode) (+16% Bus Overclock)

With all of the excellent adjustments for overclocking, we were hoping for some nice performance boosts with the Biostar. Unfortunately, that was not to happen, as the board design did not match the controls provided by Biostar. Overclocking was about the worst in the roundup, with just an 11.5% boost on a CPU that can do 20% overclocking on some boards. The lower multiplier didn't help much, allowing just a 16% boost.

Memory Stress Test Results:

Our memory stress test measured the ability of the Biostar 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. To make sure that memory performed properly in Dual-Channel mode, memory was only tested using either one dual-channel (2 DIMMs) or 2 dual-channels (4 DIMMs).

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 Biostar nForce4 boards required a 2T Command Rate with 4 DS DIMMs in two dual channels. This is the pattern seen on other top-performing Socket 939 boards, and is a limitation of the AMD on-chip memory controller. Additional voltage did not help and DDR400 with 4 DS DIMMs still required a Command Rate as we have seen on other nF4 boards.