TCCD refers to Samsung tccd IC's used on the ram. They overclock real well at lower latencies.

Ram with Samsung TCCD

Confirmed Samsung TCCD
Adata PC4500 Vitesta
Adata PC4800 Vitesta
Apacer PC4000
Centon Advanced DDR
Corsair PC3200XL
Corsair XMS PC3200C2 Rev4.1 2-3-3-6-1T
Geil UltraX pc3200 ~ Brainpower PCB
Gskill PC4400 (various) ~ Brainpower PCB ~ Not in UK (15/10/04)
Kingston HyperX PC 3200ULK2 ~ Not in UK (15/10/04)
Mushkin PC3200 Rev.2
OCZ PC3200 Rev.2 ~ Brainpower PCB
OCZ PC3700 Platinum
Patriot Extreme Performance PDC5123200+XBLK ~ Brainpower PCB
PQI 3200 Turbo 2-2-2-5 ~ Brainpower PCB
Samsung PC4000 CL3 ~ Not in UK (15/10/04)
Twinmos Twister Pro (ALL BRANDS?)

Possible Samsung TCCD
Corsair XMS PC3200C2 Rev4.2 2-3-3-6-1T
Samsung OEM PC3200

Confirmed Samsung TCCC Memory
Corsair XMSPC3700 Rev1.1

Possible Samsung TCCC Memory
Adata PC4000 (can be Hynix D43, D5)
Kingston HyperX PC4000/K2 (can be Hynix D43, D5)
Kingston Value Ram PC3200 (can be D43, D5, Samsung TCCC, TCC4)
Samsung Original PC3200 (can be TCC4)