First, to answer the #1 question popping up in comments after each ordering window closes – yes, there will be more devices available in near future (several weeks). So if you missed it this time just try again later.
Now, I belive I promised some nudes a while ago and today I finally had the time to deliver. This is for those who actually appreciate all the R&D and testing work I put into my devices.
Step 1 – research and secure suitable replacements. The one on the left I bought in unknown condition, the right one was gifted to me. Obviously I’m going to try the faster one first 🙂
Step 2 – disassemble Marty, locate the original CPU. The hard part is actually keeping track of all the screws, I like to put them back in the exact place I removed them from. Marty can have either Intel or AMD 386SX in it, I think AMD was more common since it used smaller process and run cooler with less power. At the very least the Intel one is a low power variant.
Step 3 – remove original CPU. Don’t inhale the flux smoke, label says it causes death or worse. BTW be careful not to short or overheat your CMOS/RTC battery. I have mine replaced with a holder.
Step 4 – retire old CPU. Don’t discard it in case the new one is dead or damaged. This is also why I had 2 to choose from (and a backup solution in form of an AMD 386SX on an old PC board).
Step 5 – so far so good, clean the pads. This is the most stressful step for me as it can be very easy to rip pads/traces on these older PCBs if you’re not careful.
Step 6 – solder the new CPU in, enjoy your 486SX2 Marty.
Do note that the CPU says 50 (as in, 25×2) but the actual clock is what the crystal generator next to CPU provides (32/2=16). So it’s actually 16MHz CPU still but when you enable the internal clock multiplier it will be 32MHz. And this is really the only way of doing it unless you replace the generator too – but then you’ll have problems with the rest of the mobo being overclocked, which it might not like.
Also, the clock multiplier and internal cache is disabled after reset (in order not to cause any compatibility issues) and has to be enabled by software. Which Marty BIOS won’t do, obviously. So you only get a small boost from 486 advanced pipeline but you’ll still be limited by the clock and memory bus. Game images have to be modified to include a small program to be run before the actual game executable – and that will be easier with ODE, obviously.