AOpen AK86-L UPDATE: Uncommonly Good

AOpen AK86-L: Overclocking and Stress Testing

FSB Overclocking Results

BIOS options don't mean much unless they can translate into improved performance. The AOpen AK86-L delivers overclocking as good as we have seen with this early Athlon 64 3200+.

Front Side Bus Overclocking Testbed
Default Voltage		Maximum Overclock
Processor:	Athlon64 2.0GHz	Athlon64 2.0GHz
CPU Voltage:	1.5V (default)	1.55V (Maximum vCore)
Cooling:	AMD Stock Athlon64 Heatsink/Fan	AMD Stock Athlon64 Heatsink/Fan
Power Supply:	Antec TruePower 430W	Antec TruePower 430W
Maximum OC:	2223MHz (+11%) 222FSB	2233MHz (+11.5%) 223FSB

The above overclocking setup at default voltage allowed us to reach a stable FSB of 222. As you can see, increasing voltage did not help very much, topping out at 223. These are the highest overclocks that we have seen with this Athlon 64 and we suspect 222 is the limit on air-cooling with this CPU.

By dropping multipliers in the BIOS, we were able to reach FSB settings as high as 252. It appears that the AGP/PCI is ratio controlled and that it again drops to 33/66 at a setting of 234. This means the 252 is a PCI/AGP overclock of about 19 which is in-line with the maximum overclock our picky ATI 9800 can handle. This is not a working PCI lock as we have seen on Intel chipsets; it is a ratio-driven PCI/AGP frequency similar to the one we first saw on the Abit K8T800 motherboard.

Front Side Bus Stress Test Results:

As part of normal overclocking tests, a full range of stress tests and benchmarks were run to ensure the AK86-L was stable at each overclocked FSB speed. 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. Finally, we ran our benchmark suite, which includes Veritest Winstone 2004 suite, Unreal Tournament 2003, SPECviewperf 7.1, and Aquamark 3. 222MHz was the highest overclock that we were able to achieve with the AOpen while running these tests at default voltage.

Memory Stress Test Results:

The memory stress test is very basic, as it simply tests the ability of the AK86-L to operate at its officially supported memory frequency (400MHz DDR) at the lowest supported memory timings that our Mushkin PC3500 Level 2 or OCZ PC3500 Platinum Ltd Modules will support. Memory stress testing was conducted by running RAM at 400MHz with 2 DIMM slots filled.

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

We had no problem running 2 DS 512MB DIMMs of our standard Mushkin PC3500 Level2 or OCZ PC3500 Platinum Ltd in the AOpen AK86-L. Both of these memories were completely stable at the default memory voltage of 2.5V with the fastest 2-2-2-6 timings at DDR400.

Filling all available memory banks is more strenuous on the memory subsystem than testing 2 DIMMs. AOpen states clearly that only 2 DIMMs are supported at DDR400 speed, but we decided to try 3 DIMMs at that speed. At first, we thought 3 DIMMs were working fine in this board, but the AOpen BIOS had automatically lowered memory speed when 3 DIMMs were detected. We then forced DDR400, but could not get 3 DIMMs to work at this speed. By lowering the memory speed to DDR333, or setting to Auto and allowing the AOpen BIOS to manage the speed, we were able to run 3 DIMMs at fastest timings at DDR333. We did not have 1GB DIMMs for testing to check the AOpen claim of 2GB support for DDR400 and 3GB at DDR333.

Stable DDR400 Timings - 3 DIMMs (3/3 DIMMs populated)
Clock Speed:	166MHz
Timing Mode:	N/A
CAS Latency:	2
Bank Interleave:	N/A
RAS to CAS Delay:	2T
RAS Precharge:	6T
Precharge Delay:	2T
Command Rate:	N/A

We tested the memory timings with 2 banks filled using several stress tests and general applications to guarantee stability. 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 AK86-L at these memory timings. These memory performance results are much better than we normally see with K8T800 chipset motherboards.