Pata Vs Sata hdd................

Serial ATA is the way to go! The transition from SATA to IDE drives has more than 50% complete in the market. All power supplies now come with the SATA power connectors. Most motherboards now have built-in SATA controllers. Most of them even provide SATA cables.SATA hard drives are faster, use smaller cables, and cost about the same as the IDE drives now. These have made the choice easier. Half to one year ago, this was not quite clear.

Normal hard drives like we are all used to using are Parallel ATA (PATA). There is a new standard called Serial ATA which boosts transfer speeds up to 150MBs [and up to 300MB/s bursts with SATA2 technology) as opposed to a max of 133MBs with parallel interface. The SATA standard also improves airflow in the case because wide ribbons are no longer needed and a somewhat thin compact cable is used instead. Additionally, SATA2 offers a few features like Native Command Queuing, eSATA and other. However - using SATA means you will need a SATA controller, a SATA drive, and a SATA power cable/adapter (often not included on power supplies yet). The actual speed improvement of SATA vs PATA is not much noticeable with current drives unless you are talking about the high end SATA drives using RPMs higher than 7200 which can burst through a wider channel than PATA. If you are building an average/upper end system there is currently no pressing reason to go SATA unless you are building for the future. PATA standard is slowly dying out and high-end motherboards stop even including PATA support for hard drives, they still include one, though, for CD-ROM/DVD-ROM drives that are still in their majority use PATA interface.

However, be careful in where you buy. Some manufacturers have restrictions on how warranty is done with OEM hard drives. Some of them only honor the three-year warranty if they are purchased from an authorized distributor or registered reseller.

There is only a small price difference among 80, 120 and even 160 giga hard drives. It is suggested getting as large a hard drive as possible if you don't care to spend $10 or $20 more for 20 or 60-80GB more space! That's cheap! Especially consider a 8 or 12GB hard drive used to cost $120 only a few years ago.

If you are working with a limited budget a 80GB or 160GB drive is plenty for many people! However, nowadays people buy 320GB more often because this size offers the best price per Gigabyte for now.

Speed of today's hard drives are around 7200 RPM (that is rotations per minute). Previous generation offered 5400 RPM and this speed is becoming rare for desktop drives but is a new feature for notebook hard drives. Hard drives with 7200RPM is a good choice today. Raptors (a special model of Western Digital) offer up to 10,000 RPM and are very fast SATA drives, though they are a bit pricey for a regular customer but a must for a performance PC.
Hard drives can be noisy, they rotate faster than previously. However, each manufacturer has their own technology to reduce the sound. Some work better than others. When choosing a hard drive look for special notes attributed to reduced noise in the premium models. A low noise hard drive is worth its extra price in the long term.

Many new PATA and SATA hard drives offer a bigger cache than usually. Older hard drives were offering 2MB-4MB and new generation is offering 8MB-16MB of internal memory in the hard drive itself. This "cache" memory is a buffer for recently read information and if the file is read sequentially then hard drive can simply send out data from the buffer rather than re-reading it again.

Ultra DMA EIDE is a fast technology, with an average access time of 9-12ms. (Ultra DMA is another name for ATA such as ATA66/100/133 on PATA) In comparison, SCSI II (often also referred as Ultra or narrow SCSI) hard drives typically have an average access time of 8ms-9.5ms. In our opinion it is not worth the extra money to go with SCSI II. The standard PATA drives using ATA100/133 speeds are just fine for most applications. You can also get a small boost by using the new SATA standard. Some SATA drives using high RPMs may have better access times as well (compared to PATA). SCSI is considered a professional hardware and is much more expensive than SATA or PATA solutions, also, it takes a bit more effort to install SCSI and make it all work.

RAID can be used either to increase drive performance(RAID 0), improve data integrity (RAID 1), or some of both (RAID 10). For RAID you need 2 or more similar drives and a RAID Controller which can either be in the form of a card, integrated motherboard feature, or software (server operating systems). Those looking for extra performance, and those doing large applications such as Database/Server work are encouraged to look into these Redundant Arrays of Independent Disks. RAID controllers exist for both EIDE & SCSI. More likely than not that every motherboard with a price tag of $80 and above will have some sort of on-board RAID capability for SATA drives.

Most common among users is the RAID 0. You would need 2 drives of the same size (hopefully of the same model) and capability to run RAID on your hardware. "RAID 0" writes a half of data on one drive and another half on the other drive. Thus, it takes nearly half the time to record or read data in such a setup. Problem is when one drive fails then the data on the second hard drive becomes unusable and, thus, loss of one hard drive results in a total loss of all information.
The solution to RAID 0 lack of redundancy problem is to feature a third hard drive that will record byte differences and the ability to easily recover data if any of the 3 hard drives fail becomes possible. This is RAID 10.
Those who are afraid to lose any data even with a single drive the mirror RAID 10 comes into play. It requires 2 similar hard drives where all of them have the same data. Thus, if one drive fails then another will still have all the information.
Nevertheless, any RAID solution does not become a substitute for back-up. Best back-up drive is external that is connected during back-up and kept away from the system any other time. This is done in case of fire or water damage. Rarely a system suffers from a power failure that destroys all the components. If the back-up drive is kept in the server, it would be a toast also.
If you are serious about access speed for running databases and servers, consider using Ultra-wide SCSI III (often referred to as "wide"), which have a typical access time of 7.1-7.5ms.