RAID is the acronym for Redundant Array of Inexpensive Disks. It is a method that utilizes multiple identical hard drives to exceed the performance of a larger and more expensive hard drive.

There are several forms of RAID, but the one that can give you the best performance boost is RAID 0, also known as Disk Striping.

What RAID 0 does is simply dividing the data evenly between two or more drives so that the workload is spread out among the drives. Instead of one hard drive doing all the work seeking and finding information, copying and moving it, there are two or more drives now sharing the workload.

In RAID 0 setup, a file is divided into many small parts (by default, each part is of size 128Kb). When the system writes data to a two drives setup, it will write the first part to the first drive, the second part to the second drive, the third part to the first drive, fourth part to the second drive and so on until the entire contents of the file have been written. If there are more than two drives, the data writing will be split among the drives evenly.

By utilizing multiple drives, the system can now write and retrieve data at a much faster speed. A two drives RAID 0 setup can increase speed up to 25% while a three drives setup can boost speed about 33%.

While using RAID 0, it is best to use two identical hard drive of the same storage size. Keeping in mind that the workload is being balanced, the computer can only deal with data as big as the smaller hard drive. If you have an 80 GB and a 120 GB drive in RAID 0, the computer can only treat them as two 80 GB drives, ignoring the extra 40 GB of space on drive two. You don’t want to spend money on storage size that you can’t use.

A drawback to RAID 0 is that if any one drive happens to crash, all your data are lost. If you value your data, you can include RAID 1 in your setup.

RAID 1, also known as mirroring, provides the backup feature for your hard drive. When two hard drives are set up in RAID 1, the exact data are written to the two hard drives. One hard drive is use for operation while the other hard drive serves as a backup. If the main hard drive is to fail, you still have the second hard drive to fall back on. To achieve RAID 1, you need to have two identical hard drive operating at the same time (for RAID 0, it is not necessary). The only downside is that you are halving your disk drive dollar to pay for this redundancy. Two 80 GB hard drives in RAID 1 give you only 80 GB of storage rather than 160 GB.

RAID 10 (or RAID 0+1) is the integration of both RAID 0 and 1. By using 4 identical hard drives, two in RAID 0 while another two in RAID 1, you can achieve both speed and stability. While this is really the ideal configuration, the cost of buying two extra hard drives that cannot be used at all may be a price too high for some to pay. Based on your needs, you may want to judge for yourself if you want to go for RAID 0 or RAID 10 setup.

There is a variety of CD Drives in the market, namely CD drive, CDRW drive, DVD drive, DVD-RW drive, DVD+RW drive etc. It is a headache to sort out all the different brands and types in order to find the one suitable for you. This guide shows you how to choose a good CD ROM drive easily.

Media Type

Different type of ROM drive support different type of storage media. A CD-ROM can only read CD while a CDRW-ROM can read, record and rewrite data on CD. Here is a list of what type of media each ROM supports.

• CD ROM – CD reading only
• CDRW ROM – CD reading, recording and rewriting
• DVD ROM – DVD and CD reading only
• DVD+RW ROM – DVD and CD reading, DVD recording and rewriting in +RW format
• DVD-RW ROM – DVD and CD reading, DVD recording and rewriting in ?RW format
• DVD+RDL ROM – DVD and CD reading, DVD dual layer recording of +R format

DVD+RW and DVD-RW are two different standards for DVD recording. DVD+RW allow you to add and remove data without erasing the whole disk and starting over. This means that DVD+RWs can almost be treated like removable hard disks. Conversely, DVD-RW is less flexible; the whole disk needs to be erased before new data can be added.

A DVD storage capacity is 4.7GB. Dual Layer (DL) allows user to record data on two sides of the disc, thus doubling the total capacity to 8.55GB

Choose a drive according to your need. If you wants to watch DVD movie on your pc, do not get a CD drive. I would recommend getting a combo drive that supports all the different media types. It is cheaper than getting all the different drives separately and also more convenient. The drawback for a combo drive is a slower speed.

Internal or External

Internal drives are usually cheaper than external drives. External drives connect to the computer through firewire or USB2.0 and more suitable if you need to move your data around.

Speed

The speed of the drive determines how fast it transfers data to the computer. The higher the speed, the faster the transfer. You will see various speeds on the combo drive, something like "52x32x52" The first number represents the reading speed, the second number represents the rewrite speed and the last number shows the recording speed. Choose a drive with fast speed.

Conclusion

To choose a good CD drive, you must know what you need it for. If you are using it to listen to audio CD only, it is best to get the CD ROM drive whereas if you need to copy large amount of data, get a DVD burner.

Due to its large capacity, DVD will soon replace CD as data storage device. it is recommended to get a DVD burner rather than a CD Writer so you don’t have to spend money to upgrade again in the near future.

A computer hard drive is a storage media where you install and store all your programs and data. Generally, the bigger the memory capacity, the more data you can store. The memory capacity is usually measured in gigabytes. Currently in the market, you can find hard drive that range from 10GB to as high as 750GB.

Over the years, hard drive technology has improved greatly. While its storage capacity has increased, other aspect such as its transfer speed, interface type, buffer etc. has also improved to a great extent. When choosing a computer hard drive, the things that you should look out for are the buffer, storage capacity, drive interface and the RPM.

Buffer

Every hard drive has a small amount of onboard memory that is known as buffer or cache. When data is received from the platters, it is stored into the buffer so that the next time you need to retrieve it, the data can be directly loaded from the buffer.

The bigger the buffer size, the faster the data can be accessed. Currently, the minimum is 8MB and several high end drives now come with 16MB buffers.

Disk Storage space

The storage space determines how much data you can store. The more the merrier. As a guideline, for normal usage, get a hard drive that is at least 10-20GB bigger than your current data size.

Drive Interface

The traditional drive interface is using the IDE cable. Its transfer speed range from 33MB/s to 133MB/s, depending on the motherboard and the hard drive bus specification.

Ideally, the higher the transfer speed, the better the computer performance. The transfer speed can be identified by the label Ultra DMA33, Ultra DMA66, Ultra DMA100, Ultra DMA133. The number on the label represents the transfer speed in MB/s.

Serial ATA (also known as SATA) is the next generation drive interface. The first version has a maximum transfer speed of 150MB/s and SATA II (second version) delivers 300 MB/s. A version set for year 2008 will deliver 600 MB/s.

SATA has several key advantages over the IDE (or Parallel ATA, PATA).

1. SATA has a faster transfer speed then IDE;
2. SATA uses very thin and small 7 pins connector that can go up to 1m in length, whereas IDE only allow the flat 40 wire connector that only limit to 46cm. This smaller cable length improves the air flow and heat dispersion inside the casing.
3. SATA has a lower power requirement (250mV) than IDE (5V);
4. SATA technology allows hot-swapping, which means drives can be removed or added while the computer is running. This is not achievable in IDE.

Most of the motherboards come with integrated SATA and IDE interface. For older system, third party SATA controllers can also be installed in any PCI slot to allow the system to connect to the SATA drive.

RPM consideration

RPM refers to the Revolution per Minute. The faster the disk rotates, the more data it can process. 5400rpm used to be the most common speed in the market today. Lately, hard drive manufacturers have started introducing 7200rpm hard drives to the market and the price is comparable to a 5400rpm hard drive.

Recommendation For a Good Gaming Computer Hard Drive

To get the best performance out of a hard drive, a good gaming computer hard drive must have

• A large storage space, of at least 80GB to store the game files.
• A large buffer, typically of 16MB to facilitate data caching during game play
• SATA 2 interface for maximum data transfer rate.
• A disk rotation speed of 7200rpm for maximum data processing rate

A good gaming computer hard drive that I love and strongly recommend is Seagate 320GB SATA-II Hard Drive hard drive. It is super quiet and works great under Window XP, Vista and Linux. The data processing speed is fast and I have no problem getting it to work in under 10 minutes.