UDMA mode 5 = ATA100, and UDMA mode 6 = ATA133.
Originally Posted by Bat Rastard
Yes, few drives could saturate a ATA-100 bus, and even fewer of them even crossed the 100MB/s mark sufficiently to be considered true ATA-133 drives.
(Not to mention that only a handful of manufacturers supported ATA-133/UDMA mode 6, and not all of them made devices that could saturate the ATA-133 busses).
Although, I think that most drives that were designed and manufactured towards the end of the IDE era could more or less saturate the ATA-100 bus...
The PS2 only has a ATA-66/UDMA mode 4 compatible controller. Maybe that controller can be programmed to support UDMA mode 5 and 6, but it probably isn't feasible for the following reasons:
1. The IDE cable used, in at least the SCPH-20400 HDD unit which I have, doesn't even seem to be a 80-line cable. Hence it might be possible that the IDE setup the PS2 has might not even support UDMA mode 4....
2. The IOP is too slow and has too little RAM. Even if you have a ultra-fast bus attached to it, the throughput will be affected by the IOP's slow speed and lack of RAM (Large DMA transfers are not possible).
3. I don't believe that anyone actually knows how to set the controller to communicate with the HDD at UDMA mode 5 and 6 (The Sony drivers only support up to UDMA mode 4). Otherwise, it would be a really nice fix to add to the ATAD driver within the PS2SDK.
Unmodified SCPH-77006 with SM 3.6
SCPH-39006 with M-chip modchip, SCPH-10281 NA and refurb Seagate 80GB HDD
SCPH-10000 v1.00 with SCPH-10190 PCMCIA NA and SCPH-20400 HDD unit