X-bit labs

Monday, August 15, 2005

Principles of SCSI Standard Explained. SCSI Basics Posted

BigBruin has posted an article that explains the principles of SCSI hard disk drives technology. SCSI stands for Small Computer System Interface, which can be used for connecting not only hard disk drives to computers, but also some other peripherals, such as tape drives, optical drives, printers, and scanners. The author takes a look at a few basic features of SCSI related to hard drives, and compares them to Parallel ATA and Serial ATA drives.

“Regardless of drive type, real-world performance never equals theoretical maximum values, but higher specifications imply higher potential real-world performance. Even with the latest SATA standard doubling its speed, it is easy to see that the more established Ultra320 SCSI standard has a sizeable edge in transfer rates (320 MBps > 300 MBps), in addition to the other factors that make SCSI so robust. By 2008, SATA throughput rates are expected to reach 600 MBps, but time will tell. Another speed comparison can be made between the drives in terms of how fast the disk platters spin. ATA and SATA drives generally spin at a maximum of 7200 RPM (some SATA drives now go up to 10,000 RPM), while it is standard for a SCSI drive to operate at 10,000 or 15,000 RPM. Higher rotational speeds aid in lowering times to access data, as well as when reading and writing,” writes the web-site.

• BigBruin: SCSI Hard Drive Basics.

Small Form-Factor PC Roundup Posted. Choosing the Best Socket 939 Barebone

AnandTech has issued a roundup of barebone computers. All five participants boast with different features and specifications but have one major thing in common – they are designed for Socket 939 infrastructure. The author compares Shuttle SN25P, Biostar IDEQ 330P, Shuttle XPC SN95G5, Shuttle XPC ST20G5 and Soltek QBIC 3901A-300P in terms of features, performance, overclockability, noise and temperature levels, as well as price criteria.

“We’ve already awarded the SN25P our Silver Editor’s Choice award back when we first looked at it. That award was actually given with the knowledge of how several of these other systems performed, and it still stands (more or less). If you’re looking for an all-around good performer, the SN25P packs features, performance, and overclocking support into an attractive design. The 24-bit VIA Envy sound also comes out of this roundup as the clear winner; it may not be “HD Azalia,” but it’s close enough, since it sounds better than a couple of the HD solutions that we’ve encountered. (Using digital out would of course eliminate the static on all of these systems.) Despite the complaints and concerns that we’ve listed earlier, the SN25P remains a very good SFF platform. Assuming Shuttle can get the X2 support fixed soon, the SN25P remains our pick of the 939 units. If you want to purchase an X2 processor right now, we’d downgrade the SN25P to an “Honorable Mention” until that is addressed, but the overclocking support, design, and features keep the SN25P at the head of the pack,” concludes AnandTech.

• AnandTech: SFF Roundup, Socket 939 Systems.