cant upload picture so; here is a link to one

http://www.ebay.co.uk/itm/TI-TX486SLC-E-QTY-D … =item5647f2d1f2

I would not do it for sure if I were you. The fact that you own 386sx-25 means that the mobo is from a relatively cheap, low-end system. It most certainly does not support 486 DLC, as it is meant to be an upgrade for decent 386DX-40 mobos. You are going to ruin both chips, that's all.

It might be easier for you to change you mobo to a 386DX-40 one without even getting 486DLC, as it will work almost as fine with DX. If you're looking for info on your motherboard, I recommend this: http://museum.ttrk.ee/th99/

P.S. Don't mind my grammar, English is not my mothertongue.

I don't think it will work in a 386SX motherboard, either, simply because the 386SX doesn't have as many memory address pins as a DX and an SLC/DLC will need those pins to be connected up.

A DLC wouldn't work, but an SLC is completely pin compatible with a 386SX - that's the whole point of it's existence.

yes, I have upgraded my IBM machine with a 486slc2 (originally the machine had a 386sx/20 and the slc2 works at 20/40mhz) that clips on the existing cpu

Has anyone used a straight swap of a 386 cpu with a 486 slc cpu (im not talking about the clip on upgrades just the normal chip for chip replacement?)

I just started another topic by accident.

Can the 386 be upgraded with a straight swap with a 486 slc and is there anything on the internet to show this has been done. I believe the 386 is soldered on so would require de-soldering and then soldering of the 486 slc.

Im talking about straight chip replacement rather than a clip on upgrade.

It should work, but can't say how it will perform.

Hi I was browsing and spotted this really old post.. it does work I did this with and old 386/16 laptop in the early 90's 😀

Great to read, can't agree more.

Form my experience, the compatibility of these chips is much better than expected. I tested SLC and DLC as well as clock doubling SXL2 chips for DX boards with very old motherboards with no support for these CPUs and made very good experience with the "cache486" program from the "Make IT 486 upgrade". With this tool one can enable the cache and adjust the multiplier on the fly. Thats handy if you need to boost or slowdown the systems performance for particular games.

Why is this in the Emulation forum?

Moved to Marvin.

Should be possible. I have been considering to attempt this on a 25MHz 386SX board as well (yes, you should use a 5V part, unless you have a laptop with a low voltage CPU). I would be cautious if you want to use devices that require DMA though. In order for DMA to function correctly your board needs to support either hidden refresh or have the #flush line of the CPU connected to the DMA controller. It's actually possible to modify older boards to support the latter option. The procedure is documented in the 486DLC/SLC technical manual. The other alternative is to just not enable to cache.