1. Interface of mobile hdd enclosure
Currently, there are two main interfaces for mainstream 2.5-inch mobile hdd enclosurees: USB and IEEE1394.
The USB interface mobile hdd enclosure is currently a mainstream product. Its biggest advantage is that it is easy to use, supports hot-swappable and plug-and-play, and can work normally under Windows Me/2000/XP without installing a driver. According to different standards, USB interfaces are divided into 1.1 and 2.0 standards. The biggest difference between them is the transmission speed. The transmission speed of the USB1.1 interface is only 12Mbps, while the transmission speed of the USB2.0 interface is as high as 480Mbps.
Because the USB standard is backward compatible, all current USB interfaces on motherboards can support the 1.1 standard, but the 2.0 standard is only available on the latest motherboards. Although the USB2.0 standard hard disk enclosure is about 100 yuan more expensive than the 1.1 standard, its improvement in speed and performance is a qualitative leap (when transmitting larger data, the long wait of the 1.1 standard interface is really annoying) ).
Therefore, please try to buy a mobile hdd enclosure with a USB2.0 interface. Even if your motherboard does not support it, you can leave room for future upgrades or equip it with a USB2.0 interface card.
IEEE1394 is commonly known as "FireWire". The data transmission rate of this interface can theoretically reach 400Mbps. However, since the IEEE1394 interface is not popular on today's motherboards, it is often necessary to equip an expensive dedicated IEEE1394 interface card to work. Therefore, this choice results in higher costs, is not easy to use between different computers, and is not suitable for most ordinary users. However, for some consumers who are engaged in graphics, animation, and art work, they still need the help of the "FireWire" interface to move data on MAC and PC.
Regarding the power supply of the hdd enclosure, this point is mainly for those who choose a mobile hdd enclosure with a USB interface. Since the maximum supply current of the USB port is 500 mA, at some times, it cannot meet the working requirements of some 2.5-inch hard drives. If the hard drive operates at lower than rated current for a long time, it is prone to errors or even damage. This manifests as the hard drive often losing data, being unable to complete formatting and displaying errors, and being unusable on some computers (especially laptops).
If this is the case, you can only choose a hard drive box that can use an external power supply or buy a USB-PS2 interface to take the cable. However, some hard drive boxes are designed with low-temperature built-in power supplies, which can save you the trouble of carrying an extra external transformer. If you are using an old notebook hard drive, you should also pay attention to this problem. Early model notebook hard drives tend to consume high power, with current usage ranging from 700 mA to 1200 mA.
3. Materials used for mobile hdd enclosure
The materials used in mobile hard drive boxes are something that people often overlook when purchasing. The materials mentioned here do not refer to whether the appearance of the mobile hdd enclosure is novel in design, whether it uses a colorful shell, etc., but the material used.
At present, the rotation speed of hard drives is getting faster and faster, which also brings heat dissipation problems. If the hard drive box you choose has poor heat dissipation capabilities, it will have a great impact on the stable operation of the hard drive. Currently, low-priced mobile hdd enclosurees on the market generally use plastic casings, which have poor heat dissipation effects. There may be no problem if used in a short period of time. However, if data is exchanged for a long time, problems such as data transmission stagnation, data corruption, and crashes may occur.
At present, most of the high-quality mobile hard drive boxes from regular manufacturers are made of aluminum, and some even use aluminum-magnesium alloy as the shell material. Although the price of this part of the product is higher, good heat dissipation measures will allow your hard drive to work more stably.
4. Shockproof performance of mobile hdd enclosure
The hard drive can be regarded as the most delicate part of computer accessories. Static electricity and vibration are its two biggest killers. As for the hdd enclosure as a "mobile database", shockproof is also one of its primary issues. If there are no anti-shock devices such as buffers, accidental landing or other collisions will often lead to data loss. In severe cases, physical bad sectors may occur, or even complete damage to the hard drive. Therefore, when choosing a mobile hard drive box, pay attention to whether it provides anti-shock protection. Function.
5. Design of mobile hdd enclosure
Whether a mobile hard drive box is easy to use or not, design is the key. Generally speaking, most mobile hdd enclosurees have the following designs:
(1) Heat dissipation holes: If the shell of the mobile hdd enclosure is not a good conductor of heat, it should be covered with heat dissipation holes to help the hard disk dissipate heat. However, for 2.5-inch hard drives, since the heat itself is better controlled, there is no need to worry too much in this regard. And if there are too many holes, it will also make people feel that it is easy to absorb dust.
(2) Anti-slip design: Design anti-slip patterns on the casing of the mobile hard drive box, or install anti-slip plastic pads, etc. to increase the friction of the casing and prevent the hard drive box from accidentally falling off from your hands.
6. Chip used in mobile hdd enclosure
After all, the purpose of building a mobile hdd enclosure is to "move" the data in it. Therefore, the "USB2IDE" bridge main chip used to control data "throughput" becomes even more important. It is undeniable that a good chip is much faster in transmission speed. The chips currently available on the market for mobile hard disk transmission mainly include GL811 chip, CS8813 series chip, ALi M5621 chip, ALiM5642 chip, NEC chip, Oxford chip, ISD300 chip (In-System), etc.
The price of a mobile hdd enclosure is directly related to the chip used in it. We can roughly divide these chips into three categories: high, medium and low. In terms of high-end products, among the above-mentioned chips are NEC and Oxford chips. The average cost of a single chip is about 70 to 110 yuan. In the mid-range, there are ALi chips with a cost price between 20 and 50 yuan. On the low-end side, there are chips such as GL811 and CS8813, and the cost price is only between 10 yuan and 20 yuan.