Overclocking and Stability
Within specs, the K7S5A is extremely stable, that is, it did not crash a single time during the entire testing period. At 138 MHz and even at 150 MHz the board was running quite stable as well, that is with the caveat, if it was running at all. In all cases, the critical issue was the recognition of the IBM DTLA drive by the BIOS or rather the failure to do so. Changing cables or even drives did not change this pattern that occurred regularly after loading the "Best Performance" setting and then changing BIOS settings or memory configuration. Using a different model, the IBM GXP60 (ER20A44A) the failure did not occur. There are several possibilities for this phenomenon, most likely, the "Best Performance" should be used only with the 100 MHz bus. On the other hand, once the drive was recognized by the BIOS, the error did no longer occur unless the settings were changed again. It could be a glitch of this individual board, a latent compatibility issue with the IBM GXP75 or a simple BIOS glitch but this is as much as we are able of stating at this point.
Performance
One of the domains of the SIS chipset is its non-surplused IDE performance. We used TCDLabs HDTach 2.61 to measure the performance of the IBM DTLA 207050 GPX75 Deskstar. One picture tells more that a thousand words.
One thing is for sure, the SIS chipset does not put any brakes on the IBM drive. Keep in mind that a single drive is unable to take advantage of the MuTIOL interconnect.
SiSoft Sandra Memory Benchmark
We used the 8.21 beta version of Sisoft Sandra to compare the performance with either SDRAM or DDR SDRAM. Settings were "Ultra, Best Performance" CAS latency: 2T, tRAS: 6T, tRP: 3T.
Using SDRAM (shown above), the SIS 735 chipset takes an approximately 30-40% hit in memory bandwidth compared to a DDR configuration (shown below) which seems adequate for Stream applications
| 
