50MHz 486SLC/2 A2386SX FTW!

[spirantho]

Do I get a prize for the most indecipherable yet still meaningful post title?

A while back I received a broken A2386SX bridgeboard. Once I'd removed the floppy controller chip, it sprang into life (try removing it if you get the low 1-1-3 beep error!). All 25MHz of 386SX power was available to me... but naturally the temptation of the 486SLC/2 50MHz upgrade was too much. But it was always unreliable.

Today I succumbed to another temptation - take the 386SX off and replace it.

I now have a 50MHz 486SLC/2 bridgeboard! The pictures below from DrHardware's SysInfo show the speed increase. I can now run Doom with a large window (even full screen is playable), and Ultima VII now works well.

If I can get more of the chips (I had to desolder this one from the upgrade!) I can upgrade other A2386SXs to 50MHz 486 too. The problem is getting hold of the chips. Unfortunately most 486SLC/2 chips are no good, and nor are the cheap 486SLC/e-V chips on eBay for the same reason - they're 3.3V. I need 5V 486SLC/2 chips like the GoldenGate 486SLC-2/50 uses and - handily enough - the Cyrix 386->486SLC2 upgrades use.

And in case anyone is going to ask "Why?" - because I can.

[spirantho]

I think "useful" may be streching things a bit. But it does allow me to run Win95 - although the 16-bit data bus still keeps things a bit too slow to be comfortable. Definitely not unusable, but I'd not want to use it all day. Plus it only has 8MB RAM (although I may build a SIMM adaptor to get 16MB one day).
I wonder how Linux would run on it - obviously it would need to be one of the distros meant for older machines as newer Linuces are even more demanding than Windows, but a simple Linux installation may be possible.
The hard disk is actually a 4GB Disk-On-Module, by the way, connected to a FutureIDE ISA card that supports DMA as well as PIO, so disk access is actually pretty good, which helps to make Windows usable.
If anyone does ever find a 486SLC/2 chip lying around do please let me know - getting the bridgeboard is the easy bit, it's the chip that's hard.  Unfortunately ONLY the Cyrix 486SLC/2 chip will work as a replacement, so the IBM and TI chips are useless unless they're on an upgrade board, when they can fit over the old CPU (but that's less funky )

For reference, I think this chip is roughly equivalent to a 486SX 25... but that opens up most PC software up to the mid 90's or so, which is pretty good for an Amiga!