Soltek K8TPro-939: Moving A64 to 939

Memory Stress Testing: Soltek K8TPro-939

The memory stress test is very basic. It tests the ability of the Soltek K8TPro-939 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. Memory was only tested in Dual-Channel mode 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:	10T*
Precharge Delay:	2T
Command Rate:	1T

*Several memory tests have shown that memory performs fastest on the nVidia nForce chipsets at a TRas (RAS Precharge) settings in the 9 to 13 range. We ran our own Memory Bandwidth tests with memtest86 with TRas settings from 5 to 15 at a wide range of different memory speeds. The best bandwidth was consistently at 9 to 11 at every speed, with TRas 10 always in the best range at every speed. The performance improvement at TRas 10 was only 2% to 4% over TRas 5 and 6 depending on the speed, but the performance advantage was consistent across all tests. All benchmarks were run at a TRas setting of 10.

Using two DIMMs in Dual-Channel 128-bit mode, the memory performed in all benchmarks at the fastest 2-2-2-10 timings, at 2.6V.

Stable DDR400 Timings - Two Dual-Channel (4/4 DIMMs populated)
Clock Speed:	166MHz
CAS Latency:	2.0
RAS to CAS Delay:	2T
RAS Precharge:	10T*
Precharge Delay:	2T
Command Rate:	2T

Tests with the Soltek 939 with all four DIMM slots populated were a disappointment. Since every 939 board that we tested in our 939 roundup ran at DDR400 with 4 DIMMs, we have been very surprised to find some 939 boards that will not do DDR400 with 4 DIMMs. The Epox 9NDA3+ wouldn't do it, and now, neither will the Soltek. No matter what we set, the Soltek forced DDR333 with 4 DIMMs at 2T Command Rate. No matter what memory speed we set in the BIOS, the Soltek forced DDR333 with 4 DIMMs at 2T Command Rate. We also tried 1T Command Rate, and with 1T, the board set DDR200, no matter what we set in BIOS.

Until we see a BIOS update that corrects this issue, if you plan to run four DDR400 DIMMs, then you should choose another Socket 939 motherboard.