Iwill KK266 Socket-A KT133A ATX

Overclocking Test

Overclocking with the KT133 and KT133A chipsets can be totally different experiences. With the original KT133 chipset, the FSB speed usually would not run higher than 110MHz, which is 10% above the default. As such, multiplier overclocking proved to be far more effective.

However, the KT133A chipset and its official support for 133MHz FSB is a completely different beast. FSB overclocking is now worth a closer look since FSB speeds of up to 133MHz are no longer a problem. However, we decided to find out just how high above 133MHz we could push the KT133A.

To do this, we used a Mushkin PC133 CAS2 SDRAM, and a NVIDIA GeForce2 GTS as our test bed. We started the testing by setting the CPU to run at 133MHz FSB. Then we gradually increased the FSB speed and ran tests to make sure the system was stable at that speed. If needed, we also tried to set the CAS latency to 3 and all other memory timings as slow as possible, so that the PC133 SDRAM would not be the limiting factor. Moreover, when the CPU speed got to high, we lowered the multiplier ratio setting so that the CPU is running close to its clock speed.

For the memory, we were able to obtain a stick of 128MB Mushkin High Performance Rev. 3 SDRAM. As you can read on Mushkin's site, this hand picked memory is capable of running at 150MHz with 2-2-2 memory settings. If the CAS latency settings are lowered to 3-3-3, undoubtedly the memory would be able to hit 160MHz and higher. This should be enough to reduce the memory bottleneck we had been encountering in our previous KT133A reviews.

However, since all the previous reviews were done using the "normal" Mushkin PC133 CAS2 SDRAM, we will go ahead and include results using both memory types in this review for better comparison.

Using the normal Mushkin PC133 with CAS2 and normal memory settings, the highest FSB speed we achieved was 145MHz. At that speed we could still run SYSMark 2000, Quake III Arena, and Content Creation Winstone 2000 with no problem. However, setting the FSB speed to 146MHz the system quickly became unstable.

With the same memory, we then lowered the CAS setting to 3 and reduced any other memory related settings in the BIOS, allowing us to get the FSB up to 148MHz and ran all the tests with no problem. At 149MHz, the system would not boot.