Apple this week upgraded its iMac all-in-one desktop computers with new microprocessors as well as graphics accelerators. The upgrades do not bring dramatic performance increases, but puts iMac systems’ hardware more inline with today’s needs.

The new breed of Apple iMac computers features the same design as the previous-generation as well as the same 20” or 24” wide-screen displays. The most important change to the iMac systems are new Intel Core 2 Duo processors with 6MB of L2 cache and 1066MHz processor system bus (PSB) made using 45nm process technology and available with 2.40GHz, 2.66GHz, 2.80GHz and 3.06GHz clock-speeds.

It is interesting to note that Intel Core 2 Duo 3.06GHz processor – which is available as a build-to-order option for Apple iMac – was created by Intel specifically for Apple since modern chips made using 45nm process technology operating at 2.66GHz and higher clock-speeds utilize 1333MHz bus, whereas mobile Core 2 Duo processors with 1066MHz PSB are not yet unveiled.

In addition, the new iMac machines feature 1GB or 2GB of PC2-6400 (800MHz) memory, 250GB or 320GB hard disk drive with 7200rpm motor, slot-load DVD burner, ATI Radeon HD 2400 XT or ATI Radeon HD 2600 Pro graphics card as well as other key components. The new Apple iMacs are equipped with modernized Apple Keyboard, Mighty Mouse and infrared Apple Remote. As previously, the new iMac systems feature wireless networking, built-in web-cam and so on.

Important build-to-order options for the new Apple iMac are Nvidia GeForce 8800 GS 512MB graphics card (which may also be a custom-made design since typical 8800 GS models have 384MB of memory), 750GB or 1TB hard drives, 4GB of DDR2 memory and so on.

The default configuration 20” iMac with 2.40GHz chip costs $1199, whereas the model with 2.66GHz processor features suggested retail price of $1499. The 24” iMac model starts at $1799.