Aukiman
9th May 2008, 11:08 AM
From Kailas Shastry's excellent article ....
A higher wattage SMPS always draws more power: A 600 Watt power supply does not necessarily consume more electricity by itself than say, a 300 Watt model. The higher rating only means it is capable of delivering more power when the system requires it — and at those times, of course, it would draw more power from the mains. However, during idle or periods of lower power draw from the PC, when the requirement is, say, 250 Watt, both the power supply units will consume equivalent amount of electricity. The amount of electricity consumed by the power supply for the same amount of demand from the PC also depends on the efficiency rating, which is independent of the Wattage rating. For example, a 500 Watt SMPS having an efficiency of 70 per cent can effectively deliver 350 Watt to the PC and an efficient 450 Watt unit with an efficiency of 77 per cent can match it.
Owning an all-in-one is like having a DTP center at home: Well, technically yes. After all, you can print, scan and make copies. So, on the face of it, it does look like you need not visit your neighborhood photocopier. But, once you account for the cost of ink per page, you will realize that using your home all-in-one for all tasks is not financially viable. This is especially true for cheaper inkjet models. Printing or copying an A4 sized sheet with black only text can cost you anything between US$0.07 to $0.12, depending on the printer, the mode used, etc. A photocopying shop will charge you less than $0.05 with the bonus being better print quality as well. With each purchase of a cartridge, your wallet keeps getting thinner!
A 64-bit OS will make computing twice as fast as a 32-bit one: A 64 bit operating system (OS) (and programs) has the potential to be considerably faster than a 32-bit one. But that's in theory. In real world terms however, for any performance improvement, the applications must also be 64-bit compatible. A 32-bit program will run fine on a 64-bit Windows, but you won't see any improvement in performance. A way in which a 32-bit program can benefit from a 64-bit OS is when the system has more than 3GB RAM, in which case the OS will be able to address the entire memory and make it available to the program if needed. Generally, you need a 64-bit version of your program running on a 64-bit OS to harness the full capacity of your 64 bit CPU.
You always need to 'stop' a USB device before unplugging it: This is another of those statements that's valid only under certain conditions. The idea behind saying this is to ensure that the USB device is not unplugged while data is being read from or written to it. Doing so would corrupt the file being transferred. But, if the device is idle, there is no need to go through the 'Safely Remove Hardware' drill. Note that in Windows Vista however, if you have set a USB flash drive to act as a Ready Boost device, you will need to 'stop' the device before unplugging it. For other devices such as keyboard/mouse, printers / scanners, etc., you can just unplug them provided they are not currently in use.
Switching off power without shutting down damages the PC: This must be one of the oldest debates about PCs. Many users till this day believe that switching off power without shutting down will cause physical damage to their hard drives. Our colleagues in the US PC World Test Labs conducted an informal test — they ran 30 iterations of a test, turning off a pair of systems running Windows XP without first shutting down Windows. Each time documents were left open in Word, outlook, and Quicken. After turning each PC back on, Symantec's Norton Disk Doctor and Windows disk checker found no errors. The applications suffered no problems as well. You will suffer data loss if data is being currently written (or if your work is not saved) while pressing the power button. However, if your computer hangs, and you are in a hurry to get it working, you need not be paranoid before pressing the reset button.
Repeated on-off cycles reduce the useful life of the PC: While it is true that certain components of your PC have a fixed number of start-stop cycles, those numbers are high enough not to cause worry. Microchips (including the CPU and those on the motherboard), CRT monitors and hard disks especially, have a rated number of times they can be turned on and off. Shutting the PC down when its use is not required for an hour or more will save power and even reduce component wear and tear. For example, for hard disks, this number is 50,000 or more. So, even if you switch the hard disk off and on ten times a day, after three years you would be close to 10,000 cycles, five times lesser than the rated number.
Formatting and partitioning hard disk causes physical wear and tear: When you format a storage media, the partitioning software reads and write data in multiple patterns and then fills the entire partition (or disk, as the case may be) with '0's. This constitutes a read-write operation which is no different from any other write command, like for example, copying files. During partitioning process, the starting sectors of the drive where the partition table is stored is modified. In this case also, for the hard disk, it is nothing but another write operation. When you choose a quick format option, there is even lesser strain on the hard disk as only the file table is modified to read that partition as empty. In fact, this is the reason why recovering data from a drive after quick format is a lot easier than after a full format.
Deleting files from recycle bin ensures permanent deletion: This belief is another long timer in the list of PC related myths. Emptying the recycle bin gives you a false assurance that the files are really gone. In reality, Windows only marks the area of the disk occupied by the files in question, as 'empty', but does not proceed to remove the data itself. Thus, file recovery software can search the hard disk for files that are still present (after deletion). So long as the disk area of the file is not overwritten by any new data, recovery is possible. If you wish to delete sensitive files permanently such that they cannot be recovered, use a third party tool like eraser (included on this month's DVD).
The size of the page file must be set to twice the amount of RAM: Back in the days of Windows 95 / 98, when hard disk capacity was very limited (as little as 2 GB), this was a guideline to manually set the size of the swap file in order to eke out some performance, reduce defragmentation and save some hard disk space as well. Come larger and faster hard disks, no one really bothered much about swap file sizes. The little rationale that the above swap file rule had, is no longer valid. Today, you can let Windows manage swap files on its own or manually assign the first partition of your hard disk (fastest) for page file usage.
Magnets can destroy data on storage devices: This is true only for the sensitive floppy drives — place a powerful magnet on them for some time and bid good bye to your data. But then, who uses floppy drives these days? Flash drives are not made up of magnetic media and hence are immune to magnets. Hard drives can be affected by magnets — really strong magnets. The kind that are used in laboratories, the kind that might suck the iron out of your blood. Magnets found in homes, including those in speakers are simply not powerful enough to penetrate the magnetic shield of the hard disks and harm them. In short, no magnet in your home will cause you any data loss.
LCD monitors are not suitable for games and movies: This is not a myth per se as this was largely true till about two years back. Most LCD monitors lacked contrast, had poor response time and color reproduction was not spot-on either. A lot has changed over the last two years and today an LCD monitor can produce better quality images (read: higher contrast and color reproduction for movies) and has response times that are suitable for gaming. Going the LCD way is a wise choice for more than one reason. For one, it causes significantly lesser eye strain which makes it ideal for gamers who spend long hours staring hard at the monitor. Widescreen LCDs are suitable for movies which are increasingly coming in a widescreen format too. But watch out, there are quite a few LCD monitors out there that we can classify as sub-par in quality. Do read up reviews before you get one!
CD / DVD Media can last forever: Some disc manufactures claim shelf life of over 100 years for optical media, but that is only under ideal storage conditions, use of best materials and an error free process of writing data onto it. These three conditions are seldom fulfilled, and it is not rare to see CDs and DVDs burnt five years ago going bad by mere shelf storage (not used). It is hard to predict the shelf life of optical media, and there is much disagreement between manufacturers and researchers on the subject. If data is critical to you, it is best to make a second copy of it and replace it every two — three years. Store discs away from sunlight heat and dust, as these can accelerate the aging process.
A higher wattage SMPS always draws more power: A 600 Watt power supply does not necessarily consume more electricity by itself than say, a 300 Watt model. The higher rating only means it is capable of delivering more power when the system requires it — and at those times, of course, it would draw more power from the mains. However, during idle or periods of lower power draw from the PC, when the requirement is, say, 250 Watt, both the power supply units will consume equivalent amount of electricity. The amount of electricity consumed by the power supply for the same amount of demand from the PC also depends on the efficiency rating, which is independent of the Wattage rating. For example, a 500 Watt SMPS having an efficiency of 70 per cent can effectively deliver 350 Watt to the PC and an efficient 450 Watt unit with an efficiency of 77 per cent can match it.
Owning an all-in-one is like having a DTP center at home: Well, technically yes. After all, you can print, scan and make copies. So, on the face of it, it does look like you need not visit your neighborhood photocopier. But, once you account for the cost of ink per page, you will realize that using your home all-in-one for all tasks is not financially viable. This is especially true for cheaper inkjet models. Printing or copying an A4 sized sheet with black only text can cost you anything between US$0.07 to $0.12, depending on the printer, the mode used, etc. A photocopying shop will charge you less than $0.05 with the bonus being better print quality as well. With each purchase of a cartridge, your wallet keeps getting thinner!
A 64-bit OS will make computing twice as fast as a 32-bit one: A 64 bit operating system (OS) (and programs) has the potential to be considerably faster than a 32-bit one. But that's in theory. In real world terms however, for any performance improvement, the applications must also be 64-bit compatible. A 32-bit program will run fine on a 64-bit Windows, but you won't see any improvement in performance. A way in which a 32-bit program can benefit from a 64-bit OS is when the system has more than 3GB RAM, in which case the OS will be able to address the entire memory and make it available to the program if needed. Generally, you need a 64-bit version of your program running on a 64-bit OS to harness the full capacity of your 64 bit CPU.
You always need to 'stop' a USB device before unplugging it: This is another of those statements that's valid only under certain conditions. The idea behind saying this is to ensure that the USB device is not unplugged while data is being read from or written to it. Doing so would corrupt the file being transferred. But, if the device is idle, there is no need to go through the 'Safely Remove Hardware' drill. Note that in Windows Vista however, if you have set a USB flash drive to act as a Ready Boost device, you will need to 'stop' the device before unplugging it. For other devices such as keyboard/mouse, printers / scanners, etc., you can just unplug them provided they are not currently in use.
Switching off power without shutting down damages the PC: This must be one of the oldest debates about PCs. Many users till this day believe that switching off power without shutting down will cause physical damage to their hard drives. Our colleagues in the US PC World Test Labs conducted an informal test — they ran 30 iterations of a test, turning off a pair of systems running Windows XP without first shutting down Windows. Each time documents were left open in Word, outlook, and Quicken. After turning each PC back on, Symantec's Norton Disk Doctor and Windows disk checker found no errors. The applications suffered no problems as well. You will suffer data loss if data is being currently written (or if your work is not saved) while pressing the power button. However, if your computer hangs, and you are in a hurry to get it working, you need not be paranoid before pressing the reset button.
Repeated on-off cycles reduce the useful life of the PC: While it is true that certain components of your PC have a fixed number of start-stop cycles, those numbers are high enough not to cause worry. Microchips (including the CPU and those on the motherboard), CRT monitors and hard disks especially, have a rated number of times they can be turned on and off. Shutting the PC down when its use is not required for an hour or more will save power and even reduce component wear and tear. For example, for hard disks, this number is 50,000 or more. So, even if you switch the hard disk off and on ten times a day, after three years you would be close to 10,000 cycles, five times lesser than the rated number.
Formatting and partitioning hard disk causes physical wear and tear: When you format a storage media, the partitioning software reads and write data in multiple patterns and then fills the entire partition (or disk, as the case may be) with '0's. This constitutes a read-write operation which is no different from any other write command, like for example, copying files. During partitioning process, the starting sectors of the drive where the partition table is stored is modified. In this case also, for the hard disk, it is nothing but another write operation. When you choose a quick format option, there is even lesser strain on the hard disk as only the file table is modified to read that partition as empty. In fact, this is the reason why recovering data from a drive after quick format is a lot easier than after a full format.
Deleting files from recycle bin ensures permanent deletion: This belief is another long timer in the list of PC related myths. Emptying the recycle bin gives you a false assurance that the files are really gone. In reality, Windows only marks the area of the disk occupied by the files in question, as 'empty', but does not proceed to remove the data itself. Thus, file recovery software can search the hard disk for files that are still present (after deletion). So long as the disk area of the file is not overwritten by any new data, recovery is possible. If you wish to delete sensitive files permanently such that they cannot be recovered, use a third party tool like eraser (included on this month's DVD).
The size of the page file must be set to twice the amount of RAM: Back in the days of Windows 95 / 98, when hard disk capacity was very limited (as little as 2 GB), this was a guideline to manually set the size of the swap file in order to eke out some performance, reduce defragmentation and save some hard disk space as well. Come larger and faster hard disks, no one really bothered much about swap file sizes. The little rationale that the above swap file rule had, is no longer valid. Today, you can let Windows manage swap files on its own or manually assign the first partition of your hard disk (fastest) for page file usage.
Magnets can destroy data on storage devices: This is true only for the sensitive floppy drives — place a powerful magnet on them for some time and bid good bye to your data. But then, who uses floppy drives these days? Flash drives are not made up of magnetic media and hence are immune to magnets. Hard drives can be affected by magnets — really strong magnets. The kind that are used in laboratories, the kind that might suck the iron out of your blood. Magnets found in homes, including those in speakers are simply not powerful enough to penetrate the magnetic shield of the hard disks and harm them. In short, no magnet in your home will cause you any data loss.
LCD monitors are not suitable for games and movies: This is not a myth per se as this was largely true till about two years back. Most LCD monitors lacked contrast, had poor response time and color reproduction was not spot-on either. A lot has changed over the last two years and today an LCD monitor can produce better quality images (read: higher contrast and color reproduction for movies) and has response times that are suitable for gaming. Going the LCD way is a wise choice for more than one reason. For one, it causes significantly lesser eye strain which makes it ideal for gamers who spend long hours staring hard at the monitor. Widescreen LCDs are suitable for movies which are increasingly coming in a widescreen format too. But watch out, there are quite a few LCD monitors out there that we can classify as sub-par in quality. Do read up reviews before you get one!
CD / DVD Media can last forever: Some disc manufactures claim shelf life of over 100 years for optical media, but that is only under ideal storage conditions, use of best materials and an error free process of writing data onto it. These three conditions are seldom fulfilled, and it is not rare to see CDs and DVDs burnt five years ago going bad by mere shelf storage (not used). It is hard to predict the shelf life of optical media, and there is much disagreement between manufacturers and researchers on the subject. If data is critical to you, it is best to make a second copy of it and replace it every two — three years. Store discs away from sunlight heat and dust, as these can accelerate the aging process.