Well, my motherboard broke again and needed to be RMAed. That said, I was bored and decided to lap my SI-128. This (and the next five posts) contain that tale.
1) Tape down some cling wrap to the counter to facilitate cleanup.
2) Gather all equipment needed.

3) Clean HSF with isopropanol and Kim wipes.

4) Start lapping with about a half teaspoon of water on 400-grit sandpaper. You will notice that only material on the outside is coming off, leaving the middle untouched.

I think it safe to say the sandpaper is dead.

CPU AMD Athlon64 X2 5400+ BE (NAAFG 0830FPCW) |
Motherboard DFI LANParty DK 790FX-M2RS |
Memory 2x2048 MB G.Skill DDR2 800 (F2-6400CL4D-4GBPI) |
Graphics Card 2x Diamond Radeon HD 3850 512 MB Ruby Edition |
Hard Drive Hitachi Deskstar 750 GB SATA-II; WD 80 GB SATA-I |
Sound Card Creative Soundblaster X-Fi Platinum |
Power Supply Antec TruePower Trio 650 / APC Back-UPS XS 1500 VA |
Case Thermaltake Xaser V Damier V5000A |
CPU cooling Lapped Thermalright SI-128 with Silverstone FM-121 |
GPU cooling Stock Ruby Edition |
OS Vista Ultimate x64 SP1 |
Monitor Dell Ultrasharp 2707WFP |