I am about to upgrade my mobo/cpu/ram in the very near future and have decided to go with the XP 2100+ TBred B and EPoX 8RDA (the 8RDA+ isn't available in Australia as yet).
I have recently advised a mate to buy the same and to my jealousy, he bought them. He is only using the stock HSF that come with the 2100+, only he has lapped it and used thermal paste. He is running 40deg C idle and not much over that at load even overclocked at 13 x 166, which is stock 2700+. He is only using 1.65v core, which is only .05v over stock, but the same as the higher TBred B's, so effictivly that is stock. He is happy with this at the moment and really has no need to go higher. I think he is saving up for some DDR400 so RAM won't be an issue if he goes any higher.
If those results aren't convincing enough, I don't know what is!
Intel Celeron 850 || Gigabyte 6VM7A+ || Chaintech 128mg GeForce4 ti4200 AGP8x || 256mg 128mg PC133 || 40gig Seagate 5400rpm || 40x12x48 LiteOn ReWriter || 52x SONY CDROM || 10/100M Realtek NIC