For the purpose of research, I decided to try to configure a Dell system that was as close possible to the specs of the 24" iMac that the original poster mentioned in his/her post. They still have some notable differences, but close enough for the purposes of the comparison. (All products and their respective prices are American.)
iMac 24"
Operating system: Mac OS 10.5 (Leopard)
Processor: Intel Core 2 Extreme 2.8 Ghz
RAM: 2 x 1 GB 667 Mhz DDR2 SDRAM
Hard drive: 500 GB SATA
Optical drive: 8x DVD (DL/SL) +/-RW, CD+/-RW
Keyboard: Apple Keyboard
Display: Built-in 24" widescreen glossy LCD
Video card: ATI Radeon HD 2600 PRO w/ 256 MB VRAM
Modem: None
Web cam: Built-in iSight
Networking: 10/100/1000 Base-T
Wireless: 108.11g (54Mb/s)
Bluetooth: Built-in Bluetooth 2.0
Included software: iLife '08
Warranty / tech support: 1 year warranty, 90 days phone support
Total price:
$2,229
Dell XPS 720
Operating system: Vista Business
Processor: Intel Core 2 Extreme 2.93 Ghz (factory overclocked)
RAM: 2 x 1 GB 1066 Mhz (factory overclocked)
Hard drive: 500 GB ATA
Optical drive: 16x DVD (DL/SL) +/-RW, CD+/-RW
Keyboard: Dell USB Keyboard
Display: Included 24" Dell widescreen LCD
Video card: nVidia GeForce 8600 GTS w/ 256 MB VRAM
Modem: None
Web cam: None
Networking: 10/100 Base-T
Wireless: Netgear USB wireless adapter 108.11g 54Mbps
Bluetooth: None
Included software: Trend Micro Security (15 months), Adobe Acrobat Reader 8.1
Warranty / tech support: 1 year warranty, 1 year phone support
Total price:
$3,402
Now, this doesn't mean at all that Apple PCs tend to be cheaper than Dell's. But in this particular instance, it does seem to be the case.
As for the original question, just do some research. This website lists some of the main differences, although it does seem to be a bit biased in some areas:
http://www.macvspc.info/ "Technological progress is like an axe in the hands of a pathological criminal."
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