I multimetered the supply before I used it and it outputs between 11.8v and 12.1v. Which seems good enough for my liking.

I might just keep using it on DSL, snag a ethernet PCMCIA card from somewhere and wait until christmas. New ThinkPad for christmad FTW

Ok, I think I've fixed it (sorta)

I'm using a ATX PSU to power the TP now. I'm using the 5V rail, as it seems safest and it can output up to 10 amps which should be ample for it.

Half an hour and counting

I'm on the very laptop now, posting this from Windows 98. I guess the power supply I was using before was undervolting/not enough currenting and cutting out when it was under load. I even installed Firefox, opened 5 tabs of Youtube and installed Windows Update and it still worked albeit slowly!

Thinkpads are unkillable!

Thanks for the help everyone.

But what's it like under load, and what happens to it when the laptop shuts down? 2amps doesn't seem like very much for a laptop.

Thats exactly what I'm thinking now. I guess it was undervolting and cutting out under load because there simply wasn't enough power there.

Still working three hours after on the ATX PSU. Might try and make a nice looking box for it and make it into a power brick

Could try one of them there micro-atx style mods. How big is the screen? Would it fit in an vintage Mac? That should please a few people on here

Nah, bugger that. ThinkPad chassis is win, vintage Mac chassis is not.

I like it as it is because it's still a laptop. Admittedly not a very portable laptop, but I can still lay in my bed while browsing the web.

I'm going to Maplins tomorrow. I might see if they have anything like a 3-5 amp 12v charger for something and mod that into the laptop. In fact I could even desolder the charger jack from the mobo, solder two wires to it and run these to the battery compartment. Then I could use the old charger jack to power the laptop.

I have other ideas for my old Blue + White Powermac G3 case though