Though not cited in our Summer 1999 ATA Drive Roundup as the Editor's Choice, the Quantum Fireball Plus KA was nevertheless a great performer, groundbreaking in some ways. Quantum's first 7200rpm ATA drive, the KA borrowed many elements from the design of the Atlas IV, an enterprise-class SCSI disk. Thus, its most notable strength was a low access time. Though advertised with an 12.6 millisecond access time (8.5 milliseconds seek + 7200rpm rotational latency), the KA actually turns in a score as low as 11.4ms, holding its own with current-generation 7200rpm SCSI disks. To put this in proper perspective, the KA's access time matches and in some cases beats that of a first-generation 10k rpm SCSI drive (the Cheetah 4LP)! Complementing this commendable access time was one of the first ATA transfer rates exceeding 20 megabytes per second. These low-level scores powered the Fireball Plus KA to some respectable high-level Disk WinMark scores.

The Fireball Plus KX promises "more of the same" coupled with a higher areal density and thus higher capacities and faster transfer rates. Quantum's second 7200rpm ATA drive features 6.8 gigs per platter, yielding a flagship capacity of 27.3 gigabytes. The KX continues the tradition set by the KA, featuring an 8.5 millisecond seek time. In yet another interesting display of drive performance strategy, the KX's buffer remains at a stalwart 512k.

Reliability features-wise, the KX takes a breather and remains with technology introduced in earlier Quantum drives. Quantum's Shock Protection and Data Protection systems combine to ease diagnosis of problems and theoretically increase drive reliability. The drive is protected by a three-year warranty.

As an ATA-66 drive, the Fireball Plus KX may pose problems to some motherboards running an Award BIOS. If you don't have a dedicated ATA-66 controller, we recommend disabling ATA-66 operation with a utility to be provided by Quantum at their web site.

When stacked against the Summer 1999 ATA Drive Roundup 7200rpm Editor's Choice, the Fireball Plus KX performs admirably. The KX inches past the Western Digital Expert AC418000 by a margin of 1% in the Business Disk WinMark 99 test run under Windows 95. Results are similar in the High-End Disk WinMark, with the KX sliding ahead of the Expert by 3%. The gap increases in tests run under Windows NT 4.0. Here the Quantum triumphs by 7% in the Business Disk WinMark and a substantial 19% in High-End tests.

Interestingly, in low level tests, the KX is not quite the pioneer that its predecessor was. Though sustained transfer rates hit 23 MB/sec (an all-time high for ATA drives), access time has actually regressed by a couple milliseconds. Even so, the KX still manages to beat its advertised seek time- something that doesn't happen often.

Adaptec ThreadMark 2.0 results place the Fireball Plus KX significantly ahead of the Expert. Here the Quantum drive flies by the WD by about 27% in tests under both Windows 95 and Windows NT.

Readers may recall that we found the Fireball Plus KA to be rather loud when seeking, approaching the level of many SCSI drives. We're happy to report that the KX does seem to be a notch quieter than its predecessor. While it's no Fujitsu, the KX's noise is less obtrusive than the KA, delivering about the same noise during seeks as, say, a Maxtor DiamondMax Plus 5120. The drive operates warmly though not excessively so outside a drive cooler; attention to space and airflow will allow most users to integrate this disk into their systems without active cooling.

All in all, the Quantum Fireball Plus KX combines strong performance under both Windows 95 and Windows NT to displace the Western Digital Expert (and IBM Deskstar 22GXP) as the fastest ATA drive yet tested here at StorageReview.com. The KX does have its work cut out for it though, as next-generation units from WD, Maxtor, IBM, Seagate, and Fujitsu will all be arriving shortly. Even so, judging from current ATA market trends, it seems like you won't go wrong if you decide to go with the Fireball Plus KX.