The game benchmark scores certainly remain true to the Optimus 8500 eXP's Radeon 8500 heritage, as well as confirming the 300 MHz core does yield a bit more performance. The higher clocked core also helps the Optimus 8500 eXP move ahead of the GeForce4 Ti 4200 ever so slightly, though in real-world gameplay, the differences are mostly negligible. The most promising aspect of the Unitech board is that ATI seems to ready, willing and able to let specific 3rd-party vendors clock their high-end products in excess of retail speeds. This is quite different from the NVIDIA methodology and may give ATI and their partners a competitive edge in the future.
Since the Optimus 8500 eXP is a high-end board that already features a 300 MHz clock, it's only natural that we try and find out its top-end speed. This is a bit different than overclocking a GeForce4 Ti 4200 or 4400, as there is really no higher end product to compare it to, or to set potential overclocking targets against.
After a long trip up the MHz track, we finally arrived at a final overclock of 310 MHz for the core and 326 MHz for the memory. This is certainly not close to the relative speed increases we've found with a GeForce4 Ti 4200, but it is logical given that the 275 MHz Radeon 8500 is the highest speed ATI retail product. With the Optimus 8500 eXP, we feel that we're reaching near the limits of the core technology, especially using standard cooling and without RAM heatsinks.
To help illustrate the framerates achieved with these faster core and memory speeds, we re-ran the Return to Wolfenstein and 3DMark 2001SE benchmarks and present these results in chart form. Along with the standard Optimus 8500 eXP results, we have also included scores for the Radeon 8500 128-MB, and GeForce4 Ti 4400 and 4200. Both of these benchmark charts show that the higher clock speeds continue to bring performance improvements, though these are more apparent in the RtCW results where the Optimus 8500 eXP spanks even the GeForce4 Ti 4400.
The next two charts display the overclocked scores as a percentage breakdown, and while consistent with the previous charts, these do show decidedly different trends. While the RtCW framerates follow the standard pattern of higher percentages as the resolutions are raised, the 3DMark 2001SE results paint a more even pattern.
* Keep in mind that these overclocking results are only indicative of a single Optimus 8500 eXP card, so your overclocking mileage may definitely vary.