HP today announced two new models in its TouchSmart line of all-in-one PCs. The IQ800 series features a massive 25.5-inch touch screen display (native resolution 1920x1200) and a slot-fed Blu-ray drive.

Dell and Gateway also offer all-in-one machines, but HP offers the largest screen by far (the Dell XPS One has a 20-inch monitor with 1680x1050 resolution and the Gateway One ZX190 19-inch screen with 1440x900 resolution) and is the only one capable of displaying true HD video. HP is also the only mainstream manufacturer offering a desktop PC with an integrated touch screen.

The IQ800 series can do double duty as a TV, but it’s interesting to note that HP is not offering a CableCARD tuner that would allow consumers to connect the machine to digital cable-TV service. The machine is equipped with a dual-format NTSC/ATSC HD TV tuner, however, so it can be connected to the analog output of a cable or satellite TV set-top box.

CableCARD got off to a very rough start last year, and there is still no comparable technology available for satellite TV. The decision of a mainstream PC manufacturer such as HP to not include the technology in an otherwise perfectly suitable product could signal CableCARD’s death knell. It’s doubtful that service providers such as Comcast will mourn CableCARD’s passing, since they agreed to support only only after the U.S. Federal Communications Commission ordered them to. Comcast and their ilk would much rather force customers to buy or rent the hardware they provide.

HP announced two new models in the IQ800 series: The IQ804 ($1,899) will feature an Intel Core2 Duo T5850 clocked at 2.16GHz, 4GB of PC2-5300 DDR2 SDRAM, and a 500GB hard disk drive, and a slot-fed SuperMulti DVD burner. Graphics will be provided by an Nvidia GeForce 9300 M GS HD videocard with a 256MB frame buffer (the card can also tap up to 2GB of available system memory). HP expects to begin shipping this machine on September 21.

The upscale IQ816 ($2,099) won’t be available until October 12. It will be based on an Intel Core2 Duo T8100 running at 2.1GHz, 4GB of PC2-5300 DDR2 SDRAM, and a 750GB hard drive. This machine will come standard with both a read-only Blu-ray drive and a SuperMulti DVD burner. The IQ816 will also use an Nvidia GeForce 9300 M videocard, but with twice as much memory (512MB).

Both machines will feature integrated 802.11n wireless networking, a gigabit network interface, integrated Bluetooth (used primarily for the wireless mouse and keyboard), a built-in webcam, and a five-in-one memory card reader. HP is installing the 64-bit edition of Windows Vista Home Premium on both TouchSmart models.