Individual Components
So, where does the money go when you purchase a PC, and where will spending extra on a component make a difference? The following list shows many of the major components of a PC system and very rough price ranges for those components.
CPU: The central processing unit. Prices range from under $100 (e.g., $75 to $105 for Celerons from 2.8GHz to 3.33GHz, or $75 to $85 for a Sempron 3100 to 3300 – at time of writing) to around $1000-$1500 (for the top-end dual solutions; such as Intel’s Core 2 Duo Extreme QX6700 at $1500 or AMD’s Athlon 64 FX-62 at $1150). There is not always a linear relationship between price and performance (see the next section).
Monitor: The display screen. TFT (flat panel) are the dominant technology, with CRT (picture tube), now all but vanished. Size is measured diagonally across the screen. TFT displays tend to deliver a crisper image, consume less desk space and power, while also providing the full viewable region (most CRT monitors lose about an inch from their viewable region). Prices (for TFTs) vary from around $250 for 17”, $300 for 19” through about $450-$550 for 22” and around $1000 for 32”. Generally 17”-19” is more than sufficient. There is a range of qualities in monitors offered from any manufacturer and significant differences between some manufacturers. Things to check are native resolution and refresh rate (known as response time for TFTs).
Motherboard: The main board on which the CPU sits, and to which most components are connected. Prices range from under $100 to over $400 [typically $100-$250] dependent on type (Socket AM2, Socket 775, etc.), features, manufacturer, etc. There are significant compatibility issues between motherboards and CPUs: certain CPUs require certain classes of motherboards (issues of how the chip fits onto the motherboard and supporting chipset). Even within a class of motherboards there are differences based on the speed of transfer to/from the hard-disk (e.g., ATA-66 vs. ATA-100 vs. SATA vs. SATAII), and to/from main memory (known as the front-side bus [FSB] speed (e.g., 100MHz vs. 133MHz vs. 166MHz vs. … 1066MHz).
Case: The “container” for the computer. Prices range from $60 to over $300 dependent on quality of power supply, size, and number of slots available for peripherals. There are a number of choices based on internal dimensions (e.g., AT, ATX), which are dictated by the motherboard, and external dimensions (e.g., tower, mini-tower, desktop); which are more a question of aesthetics.
RAM: Main memory. There are two main classes of memory employed today, and the type of memory that must be used in a system is dictated by the CPU/Motherboard combination. Most modern machines employ the 184-pin DDR RAM (at 266MHz, 333MHz, 400MHz 433MHz, 466MHz) known as PC2700, PC3200 etc .; or the 240-pin DDR2 RAM at 400MHz and 533MHz. DDR/DDR2 RAM retails for prices ranging from as low as $40 for 256M (DDR - 400MHz) through $70-$90 for 512M and $130-$200+ for 1Gig. The older systems (Pentium 2 and 3, Celeron, Duron, and earlier Athlons) employ the 168-pin SDRAM, which comes in speeds of 133 and 150. 256M of SDRAM can be had for around $40 (512M: $80 - $100). CPU, Mobo, and RAM are intimately tied together – the right combination is necessary for a working system – be sure you know what you’re doing if you are purchasing individual components.
Hard Disc: Permanent storage, where your programs and files are kept. Hardrives are differentiated on the basis of size (2.5” used in laptops/notebooks, 3.5” used in desktop systems), and interface protocol – IDE, SATA, SCSCI. IDE was the dominant (and most common) form, SCSI is all but vanished, with SATA the newer (and better technology – i.e., faster transfer rates) kid on the block – SATA capable systems are now very common, with the motherboard determining whether your machine can run a SATA drive or not. Other factors that differentiate hard discs are their spin rate (revolutions per minute, either 5400, 7200 or 10000 RPM), seek time, and (for the IDE drives) transfer protocol (ATA/UATA 60/100/133). Prices (for 3.5” SATA or IDE) vary from around $60 for the smaller 80G drives, $110 for 250G, $130 for 320G, through to $250-$370 for 500G. 2.5” drives appear to max out at about 160G currently, and have a markedly higher price for the same storage capacity (when compared to 3.5”). Price tends to scale with capacity of the disc and it never hurts to have more space.
CDROM/DVDROM/CDRW/DVD RW: A CD/DVD reader (writer). Comes with a max speed as a multiple of the speed a music CD (or DVD) spins at. Current CDROMs run to 52X and 56X and retail for around $20. There is almost no benefit what-so-ever in having a faster CDROM (e.g., 56X vs. 40X). CD Burners (CD-R & CD-RW) are now common on nearly all systems, with the lowest cost burners starting around $30. DVD Writers are now also common on mid-range consumer machines and are priced around $45-$70 currently.
Video Card: Hardware dedicated to creating the image on the monitor. All modern cards have excellent 2D performance, the differentiating factor between cards being 3D performance (e.g., games). There are two classes of graphics cards based on how they connect to the motherboard – the older and now less common AGP; and the newer PCI Express. Prices range from as low as $60 for older cards such as a 128M Nvidia 6200 or ATI X550; through $75-$200 for the bottom of the range Nvidia 6600, 6800, 7100, 7300, 7600 or ATI X1300, X1600, X1650 cards, through $200-$600 (e.g., ATI’s X1950 or Nvidia’s 7900, 7950), to as much as $1000 for the latest cutting edge (Nvidia 8800). Truly dedicated gamers employ 2 high-end graphics card in a combination known as SLI (Nvidia cards) or Crossfire (ATI). There are big differences in 3D ability between graphics cards.
Sound Card: Produce stereo (or more commonly now, surround) sound and special effects through the speaker system. Prices range from $25 for the older sound cards to as much as $400, with even the cheap cards being OK for normal usage.
Keyboard: From under $20 to well over $100, with $30-$40 getting you a decent keyboard. There are different standards in connection of both keyboards and mice between older PCs and those currently offered. Wireless keyboards can be found for around $40 and up.
Mouse: From as little as $10, through to more than $100 for the modern ergonomic, multi-buttoned and featured mice. You can pick up a good mouse for $30-$50. An optical (as opposed to mechanical/ball) mouse is highly recommended. Wireless can also be found for under $25 and up.