I am a retro person and still keep a fleet of older motherboards, including several RDRAM boards. I think I can start an RDRAM museum. Interesting enough, the ole RDRAM boards such as the P4T-E and P4T533-R actually boot and shutdown WinXP faster than the last boards I bought while overclocking in 2005: FX-60 running 300x10, 2.5-3-3-6 on a DFI NF4 Ultra-D board. I don't know why this is. The P4T-E would typically be running 156/4x at 3.12 gig on a 2.0A CPU!
In regards to your question, the PC1066 were later technology so they overclocked higher than stuff like PC600 or PC800. For example, the PC800 I have max out around 144/4x. The 45 ns versions would run up to maybe 150/4x. Good overclocking PC1066 is capable of 156/4x, the max clock of the Intel 850 MBs. Bandwidth at the time was huge compared to DDR1. For a short period, the P4T533-R was available with 32-bit RIMM4200/4800. I have cherry sticks that hit 170/4x Memtest clean, but the max stability of these boards were 166/4x where the video card lost signal upon booting into Windows. Bandwidth at 166/4x was astronomical compared to other RAM technology at the time, but it was very hard to find cherry sticks of RDRAM as quality varied greatly. OCZ came out with PC1200 (16-bit) for a short period of time. These sticks were guaranteed to run 150/4x but usually did 156/4x.
I have bought some RDRAM over the last few months as spares, and they are still expensive compared to DDR2/3. Not sure it is worth it to pick up these boards. There is still demand for RDRAM, particularly 512 MB sticks, because I had to pay rather high prices to outbid people on Ebay! Five years ago a 512 MB stick would run $500; today it will run maybe $150. In addition, the P4T533-C board still commands good prices on Ebay.
