Dreamcasts are almost 20 years old now and its overdue to replace the thermal pads. Surprised the dc pads lasted this long.
Here are some decent replacements..
https://www.newegg.com/Product/Product. ... 6835186166
1.0mm Minimum- 1.5mm Recommended!
Cut to fit they come in a 50mm sheet or 145mm if you take your dc apart often I recommend getting the large sheet for extras.
Caution: Some pads are quite fragile like clay and can come apart especially if reused so be gentle.
(If these are unavailable to you I'm sure any other thermal pads that thick will do fine)
I have been using these pads for a few months and they seem to do a great job.
Don't forget to replace the Bottom pads underneath the motherboard too, they protect crucial components that are directly under the cpu and gpu they are very important. There is also a thermal pad in the gd rom drive you can try to replace that too.
Was going to post some pics but they're too big to upload? sol dc talk..
Keep your Dreamcasts cool and last forever!