Shuttle SB81P: Intel's 915G

Shuttle SB81P: Overclocking and Memory Testing

Overclocking Testbed
Processor:	Pentium 4 3.4GHz LGA775
CPU Voltage:	1.3875V (default)
Cooling:	ICE heatpipe cooling
Power Supply:	Shuttle 350W PSU
Maximum OC: (Default Ratio)	208FSB 3536MHz (+4.0%)
Maximum FSB	208FSB @ 14X multiplier

Unfortunately, Shuttle still has not found a remedy for Intel's overclock lock, something that has now been successfully breached by most retail S775 Prescott motherboards on the market. This is definitely something that needs to be resolved by Shuttle, as it would seem almost criminal for an SFF with such overclocking potential to not be able to reach near the overclocking boundaries set in BIOS. As you can see above, a 208MHz FSB overclock (4.0%) is underwhelming to say the least. Most retail S775 motherboards are getting over 260MHz FSB, with some reaching near 300MHz in special circumstances. Clearly, the SB81P isn't nearly in the same range.

Oddly enough, the Monarch Hornet Pro reached this exact same 208MHz FSB limit. We believe it's a coincidence, especially since the SB81P was able to run very smoothly at 214MHz FSB before rebooting later on after hours of stress testing. As a further reminder, we only shoot for the highest trouble-free overclocks possible in our reviews, which is why 214MHz FSB wasn't listed.

Memory Stress Test Results:

This memory stress test is very basic, as it simply tests the ability of the Shuttle SB81P to operate at its officially supported DDR memory frequency of 400MHz, at the best performing memory timings that our OCZ Platinum DDR400 modules will support. Memory stress testing was conducted by running RAM at 400MHz with 1 DIMM slot filled.

Stable DDR400 Timings (2/2 DIMMs populated)
Clock Speed:	200MHz
Timing Mode:	N/A
CAS Latency:	2.0
Bank Interleave:	N/A
RAS to CAS Delay:	3T
RAS Precharge:	6T
Precharge Delay:	2T
Command Rate:	N/A

While not the ideal 2-2-2-5 that we were looking for, 2-3-2-6 are plenty fast timings. In reality, memory timings or any other memory latency concerns really aren't terribly significant from a performance standpoint. They're nice, they're neat, and they do affect performance, but in the end they make very few visible differences. What you really should be concerned about is memory bandwidth and memory speed. That is if you want to overclock, as the SB81P doesn't "officially" support faster than 400MHz DDR speeds.