I have two 486sxl40's which are the same as the 486sxl-2-50 just rated for a lower speed. However I am confident they will work at 50 or 55Mhz bus and they don't have to be clocked doubled. Hopefully I can do that on regular air cooling. Hopefully that can be my daily driver speed. I'm not expecting a huge lift, but they say the 8kb verse the 1kb cache is worth ~7% in doom. If I can do it on air with cache enabled I will be pretty happy. Yep, clock doubling just isn't effective on the 386 bus. It is still interesting to look at. I want to put together a complete set of benchmarks for the CPU's and FPU's I have at a range of clocks and isa speeds. However, I have to say, 50Mhz is mind blowing, the machine is really quite snappy. Going back to 40mhz or 33mhz is dramatic in its slowness. At 50Mhz it starts to feel like a 486 something. I also want to do a bench at 63Mhz with the petlier. Just to see. Apparently no one has been there at that speed. I don't find the isa bus to be a huge limitation, oc your bus, oc your card. The 386 does struggle to feed it anyway. VL bus was always a pain in the arse to get good. Then your limited on most boards to 25-33mhz clocks, and even then, there are issues. At the end of it I just want a pretty snappy 386ish machine to explore the quirks of the platform. The idea was never to build the fastest. It will be happy in DOS and some win95 duties and sits in a modern case with modern peripherals.