All Aboard! P4 with 200 MHz FSB and the i875P Dual DDR400 Chipset

Higher Performance With Serial ATA?

When it comes to the question of whether or not to make the switch to Serial ATA, the performance, which is theoretically higher than with UltraATA, is certainly an important argument. Up to now, though, there have been two arguments for holding back. For one thing, there are barely any native Serial ATA devices out there. Here, we are referring to the controllers or hard drives that are not based on parallel ATA design and that do not have to fight their way through performance-hampering transformer chips, and instead support the new standard theoretically with maximum performance. For another thing, Serial ATA controllers up to now were run from the PCI bus, which doesn't really allow for maximum performance.

The third and final point is the fact that hard drives are still far off from attaining the 150 MB/s mark. Unless you work with a RAID array. Here, performance increases almost linearly.

For the test, we used two of the latest Serial ATA hard drives from Seagate (Barracuda ATA V/ ST3120023AS) as well as Maxtor (DiamondMax Plus 9/ 6Y160M0). Basically, our previous test showed that the Seagate drive, despite its native interface, does not gain any advantages from the new interface. Only one of these drives reached a maximum of 89 MB/s (interface transfer rate) with Intel's new controller. By comparison: 84 MB/s were attained with S-ATA controllers on the PCI Bus. Thus, the ICH5 offers higher performance, but the latest UltraATA/100 drives already manage to put 80 MB/s through the interface.

With regard to the maximum, we were also unable to determine this with two of the Seagate drives in RAID 0. The maximum transfer rate of ôMediumö increases, noticeably, from 42 to 75 MB/s, and the top value at the interface, 85 MB/s, was even just below the value of a single hard disk.

In the end, the qualities of the Serial ATA controllers from Intel are confirmed by the Maxtor hard drive. In spite of the fact that a bridge chip was used, this drive reached an interface transfer rate of 109 MB/s, thus surpassing the measured maximum up to now of 1 MB/s, which we attained with the help of the S-ATA controller from our previously tested Silicon Image (Sil3112) .

We'll be bringing you a more extensive test of the ICH5's Serial ATA controller soon, and we'll be sure to find out what the drive's maximum performance is.

Uwe Scheffel