However, in my college days, I have been reading the hard disk blog column of "0 and 1 Science and Technology Magazine" (written by Mr. Zhu, who is quite famous in the storage industry and has worked in Seagate for many years. I also bought his book "The Principle of Hard Drive". I don't know where it is, but I can't find it. During my tenure in a NAS manufacturer, I didn't have a chance to get a book for Brother Zhu to sign. Unfortunately, for a long time, I had unrealistic illusions about IBM hard disk "Mr. Magnetoresistive Head". Considering the price and heat dissipation, three IBM Ultrastar 2ES (model DCAS-32 160) with a capacity of 2. 16GB became my first time to taste SCSI and IBM hard disks at the same time. The reason why I will buy three at a time is also very simple: I will assign them to other computers in the future, and of course, this will also skip tickets.
Model: Ultrastar 2ES (DCAS-32 160) brand: IBM capacity: 2. 16GB speed: 5400rpm cache: 5 12kB interface: ultra-wide SCSI interface, maximum transmission rate: 40MB/s, working temperature: 55 degrees.
I have to say that IBM's ace technology "magnetoresistive head" was applied to disk drives as early as 1984, and the IBM 0663“Corsair "hard disk was first introduced at 199 1. Based on the magnetoresistance effect, the data on the disk can be read by the resistive head which is quite sensitive to the change of magnetic field, and the capacity of a single disk can be greatly improved, which is called lifting. After that, IBM introduced the non-ID sector track recording format "Zhuquan" (but it may eat up some space in the cache), further expanding the lead.
Different from the previous three generations of electromagnetic induction head technology (ferrous head, MIG head and thin film head), magnetoresistive head is only responsible for reading, while writing follows the traditional induction head, that is, "separation of reading and writing". The reading and writing methods of inductive writing and magnetoresistive reading can be optimized according to the different characteristics of reading and writing. In addition, the working stability of the magnetoresistive head has nothing to do with the disk speed, which is quite beneficial to the development of low-speed notebook computer hard disks and high-speed server hard disks.
Interestingly, at that time, it was not servers and desktops that IBM occupied the cheap market by magnetoresistive heads, but 2.5-inch notebook products (Travelstar), because it was difficult for miniaturized hard disks to expand their capacity by increasing the number of disks. Whether a single disk can carry more capacity is enough to determine the success or failure of the specification. Higher storage density ensures lower rotational speed (representing lower power consumption and stability of external installation mechanism)
It is worth mentioning that Quantum has published a series of Sirocco (Desert Storm), and the product positioning is highly coincident with the fireball. It is the company's first ATA hard disk with MR head, with a rotation speed of only 4500 rpm, but its overall performance is not inferior to that of fireball, and its noise, calorific value and power consumption are obviously dominant.
The giant MR (GMR) magnetic head introduced by IBM in 1997 also follows the same principle, but it is more sensitive and achieves higher storage density by using materials with better magnetoresistance effect and multilayer thin film structure. The first giant magnetoresistance head hard disk IBM Deskstar 16GP Titan three disks 16.8GB, which is almost the same as the quantum fireball ST 6 in the same period.
However, as the product capacity gradually exceeds the demand, consumers no longer pursue products with higher capacity in the same period. After all, the hard disk industry can't continue the old trick of "steadily increasing production capacity and maintaining product prices", and the profit of the hard disk industry continues to decline (the only turning point in recent years is that the 20 1 1 Thailand flood destroyed the hard disk supply chain, which actually allowed manufacturers to raise prices at will. At that time, Japan's PC Watch had an extremely sour title, "Enjoy the high-profit hard disk industry by flooding", which led to successive mergers and acquisitions. In 2003, IBM also sold its department to Hitachi, ending the fate of IBM and the industry that created hard disks in 1956 for nearly half a century.
I accidentally made another big mistake. How do these three DCAS 2. 16GB hard drives work?
Frankly speaking, the author thinks he is really asking for trouble. Finally, I sold the complete SCSI environment to a friend who really needed it, and then 1 IBM DHEA 6.48GB (36480GB), which was praised at that time, was donated to the community after retirement. 1 value 3, changed it cleanly, and the cabinet was no longer full of cables, which was much more refreshing.
Model: Deskstar 5 (DHEA-36480) brand: IBM capacity: 6.48GB speed: 5400rpm cache: 476kB interface: ATA-4 interface maximum transmission rate: 33MB/s (Ultra DMA 33) working temperature: 55 degrees.
God, I wasted my precious youth like this! Koko.
To be continued: The next episode "Hard Technology: Late Encounter with WD in Guanghua Computer DIY Memoirs-Noisy Hard Disk"