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Raven
May 9th, 2009, 11:38 AM
I've on the way a Compaq LTE with a 486SL at 33mhz. While this is probably sufficient, I'd like to upgrade it with an IBM 486DX4 I have sitting around when it gets here. I realize that the 486SL runs on 3.3v and an ordinary 486 on 5v, but would this be a problem? Would the 486DX4 run on 3.3v? Would the bus of the laptop be capable of 5v? Am I crazy? :P

Chuck(G)
May 9th, 2009, 12:35 PM
Isn't the 486SL a soldered-in QFP? The DX4 is a PGA package. How are you going to do this?

Forgive me if I show my ignorance. :?

IBMMuseum
May 9th, 2009, 02:01 PM
Isn't the 486SL a soldered-in QFP? The DX4 is a PGA package. How are you going to do this?

Forgive me if I show my ignorance. :?

All of the 486SLs I have known are PQFP, so I think you've hit it right...

Raven
May 9th, 2009, 03:22 PM
I didn't know.. Since my 486SX/DX laptops are all simple PGA I had assumed the SL would be as well. That's a shame.

Anonymous Coward
May 9th, 2009, 03:38 PM
It should be PQFP, but that doesn't make it an impossible upgrade. On 386SX motherboards I've successfully sliced off the chips using a utility knife, removed all of the old legs with an SMT soldering iron, and replaced the chip with a TI486SXL. The pin spacing on the 486SL should be the same as the 386SX, so I would say this procedure is doable. Naturally you'd have to be pretty confident in your soldering skills.

I'm planning to upgrade my TP750 with 486SL with an am5x86-133. There used to be businesses that did this.

Chuck(G)
May 9th, 2009, 04:16 PM
Naturally you'd have to be pretty confident in your soldering skills.

That--and how are you going to go from a SL to a DX4?

More to the point, why? Why not just pick up a cheap used P1 if performance is important?

IBMMuseum
May 9th, 2009, 06:52 PM
That--and how are you going to go from a SL to a DX4?

More to the point, why? Why not just pick up a cheap used P1 if performance is important?

Yes, it would only be for the internal clock multiplying - the 486SL has a math coprocessor on board. Really all it was is a low-power 486DX in PQFP design. It would be more interesting to me to replace a 386SX with a 486SLC2, or a PQFP 386DX with a 486SLC3.

Raven
May 9th, 2009, 08:49 PM
The only point was to go from 33 to 100mhz.. I honestly don't need the power, I just love the i486 and would love to get a portable one that pushes the platform to it's limits. Pentiums are boring, heh. The box I'm getting runs Win95 as well, and if I had been able to get to 100mhz it would've performed a tad better.

I'll likely just stick plain DOS and maybe a Win3.x copy (just for a few progs/games) on the thing..

Vlad
May 9th, 2009, 09:29 PM
I just love the i486 and would love to get a portable one that pushes the platform to it's limits.

Ever thought about seeking out a laptop with a 486? Like one of the common Toshiba/IBM ones or the uncommon Compaq Portable 486?