Wanted Snap-on 486 upgrade chip for Am386sx

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ralphmaif

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I have an Am386sx 25MHz (soldered PQFP100) I'd like to upgrade to 486slc with a snap-on solution. I performed this upgrade on my dad's office network back in the mid-90s, and it worked pretty well. I have a heat station and tools and am willing to try de-soldering/cleanup/soldering but would rather avoid that if possible.
 
Why didnt you just desolder the 386sx and solder a 486slc? What is your budget? I have Cyrix DRX2
BR,
Laszlo
 
Why didnt you just desolder the 386sx and solder a 486slc? What is your budget? I have Cyrix DRX2
BR,
Laszlo

With Wanted threads prices should be discussed in PM (DM)
 
Why didnt you just desolder the 386sx and solder a 486slc?
BR,
Laszlo

nerves. 😆

I've done enough light soldering that I feel comfortable pulling and then soldering components with several pins, but 100 of them at a go is next level. I have watched videos of folks doing just that, and I actually did pick up a Buffalo upgrade board with a 486slc/25 and a 387 FasMath. I extracted them both (the latter just needed gentle prying), so I can repurpose the 486 for sure if it comes to that. That said, if I can avoid it with a 3rd-party product, I will.
 
Dont bother!
AMD 386sx won't work with a clip-on SLC or SLC2 because it lacks the HALT pin.
You can only desolder your CPU and resolder the 486SLC instead.
 
Dont bother!
AMD 386sx won't work with a clip-on SLC or SLC2 because it lacks the HALT pin.
You can only desolder your CPU and resolder the 486SLC instead.
That is interesting... I do recall installing a snap-on solution to several Tandy boards in the early 90s that were successfully detected by the utility/cache driver that came with the kits. Admittedly, I do not recall whether those upgrades were Cx or Ti chips, but my understanding is they were often/mostly the same spec licensed by Cx but made by Ti, just branded differently. I may be a little fuzzy on some of those details.

In any event, you're of course right that soldering is the more reliable fit either way. The "486 in 6 minutes" solution is more or less unobtanium these days, so I've got a challenge to overcome either way, I s'pose.

Thanks for the reply & advice!
 
It is only the very first intel 16mhz 386sx that lacks the disable pin, all other SX CPUs after it have it - both intel and AMD
I have used clip on upgrades successfully with i386sx20 and am386sx25 and had no issues ( other than the poor contact the clip on sockets have nowdays since they are used )
 
Might depend of the revision because it didn't work at all with the AMD 386sx 25 from my GoldenGate 386 (this one have been upgraded later to 486SLC2). Lack of HALT.
 
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