Unreal on a 1MB Pentium Pro - 200MHz vs. 233MHz
When I was getting started benchmarking various Pentium MMX overclocking configurations, the one game I intended to test but ended up leaving out was Unreal, largely due to issues with capturing any video output in that game specifically. To summarize what little I ended up testing with it, raising the CPU's clock multiplier itself doesn't do much because Unreal seems to be dependent on L2 cache speed, and possibly size as well.

Speeding up the L2 cache on a Socket 7 motherboard would require raising the front side bus clock, but in contrast, the Pentium Pro's on-package L2 cache always runs at the same speed as the CPU clock itself. As a result, raising the clock multiplier even by 0.5x will provide very significant performance scaling for applications that heavily rely on L2 cache in some way; in this case, the jump from 200MHz to 233MHz results in a gain of almost 5 frames per second in Unreal. I'd really like to push the Pentium Pro further, but I don't have any large heatsinks for it handy, and it's just not as strong of an overclocker as the Pentium MMX. I've read on Vogons that capacitors can be soldered onto the gold top (256K/512K) variants to stabilized them at higher speeds like 266MHz.