How small can i go?

[haha49]

im looking at building a computer thats basicly mb usb hardrive and small dvd rom as a computer but ive been looking and im haveing a hardtime find really small computer parts i see alot of micro atx stuff but i want as small as i can go and still be able to run xp basicly.. Im going to install the operating system on an sd card so i just plug it in and theres my computer basicly.. i want a slot loading dvd or maby laptop dvd rom

[Crazy Buddhist]

You can find mini-ITX 17cm x 17cm MOBO's with all you need including up to Quad core processor support. Micro-ITX boards are even smaller 10cm x 17cm. 17cm is 6.7" (inches)

This means you could build the whole thing including the DVD drive in a box 7" square and about 3" high. Small enuf?

Here (http://www.logicsupply.com/products/lv_675d_s) is an example of a 17cm x 17cm board at $99 and this is what you get for those $99:

Processor Supports Pentium M/Celeron M Socket 479
400/533 MHz FSB up to 2.26 GHz
Chipset Intel 845G north bridge
ICH4 south bridge
System Memory 1 DDR333/266 SDRAM sockets
Up to 1 GB memory size
VGA Built-in Intel Extreme Graphics
Onboard DVI connector
Expansion Slots 1 PCI
2 Mini PCI
Onboard IDE 1 Enhanced IDE (40-pin)
1 ATA 100 (44-pin)
Onboard USB 4 USB 2.0
Onboard LAN Intel 82541PI 10/100/1000
Onboard Audio Realtek ALC665 AC'97 codec
Onboard TV Out S-Video and Composite TV-out
Onboard 1394 IEEE 1394 Firewire
Back Panel I/O 1 VGA port
1 LAN port
2 USB 2.0
1 Parallel port
3 Audio jacks: line-out, line-in and mic-in
1 S/PDIF optical audio
1 PS2 mouse port
1 PS2 keyboard port
1 IEEE 1394 Firewire
1 TV-out port
1 S-Video port
Onboard I/O Connectors 2 IDE connectors (40-pin and 44-pin)
1 RS-232 COM connector
1 RS-232/422/485 connector
1 Slim FDD connector
1 USB 2.0 connector for 2 USB ports
1 GPIO connector
1 S/PDIF connector
1 CD audio input
1 IRDA connector
Wake-on-LAN connector
1 Front panel audio connector
1 CD audio-in connector
2 Fan connectors
BTX power connector (24-pin)
BIOS Award BIOS 2/4Mb flash memory
System Monitoring & Management CPU voltage monitoring, Wake on LAN, Keyboard power on, Timer power on, System power management, AC power failure recovery
Operating Temperature 0 ~ 60°C
Form Factor Mini-ITX (17cm x 17cm)
Includes ATA 133 flat cable (40-pin, 80 conductor,
3 connectors)
ATA 133 flat cable (44-pin, 44 conductor,2 connectors)
Installation CD
User manual
Heat sink with fan
DVI connector (with cable)
Slim type floppy cable

http://www.logicsupply.com/images/photos/mainboard/LV-675_pic1_big.jpg (http://www.logicsupply.com/products/lv_675d_s)

Click on the image to go to "Logic Supply's" website where I got the info and the item is for sale. I have done 2 minutes research here though .... have a good dig around and you might come up with something better for your needs.

EDIT: Ooh look ... a Motherboard that is 10cm x 7.2cm (http://www.mini-itx.com/reviews/pico-itx/default.asp?page=1) ... thats 3.9 x 2.8 inches and it includes:

Processor Supports VIA C7 1.0GHz NanoBGA2 Processor
Chipset VIA VX700 Advanced All-in-One System Processor
Memory 1 x DDR2 533 SODIMM slot underneath board (up to 1 GB)
Graphics Integrated UniChrome™ Pro II 3D/2D AGP with MPEG-2/4 and WMV9 Video Decoding Acceleration
Audio VIA VT1708A High Definition Audio Codec
LAN VIA VT6106S 10/100 Mbps Fast Ethernet Controller with Power Management Functions
Back Panel Connectors

1 RJ-45 LAN port
1 VGA Port
Onboard I/O Connectors

1 UltraDMA 133/100 connector (2.0mm 44-pin connector)
1 Serial ATA Connector
1 USB pin connector for up to 4 USB 2.0 ports
1 10-pin COM pin connector
1 PS2 mouse/keyboard pin connector
1 16-pin Front Panel Connector
1 3-pin CMOS Reset Jumper
1 6-pin PS2 mouse/keyboard pin connector
1 40-pin LVDS/DVI panel pin connector
1 18-pin Audio pin connector for Line-out, Line-in, MIC-in, S/PDIF in, and 7.1 Channels Audio Output
1 80-pin Multimedia connector to support External TV-Out Interface, Video Capture Port Interface and Low Pin Count Interface. (One VT1625M add-on card is required.)
1 12-pin Pico-ITX power connector
Award BIOS LPC 4/8MBit Flash Memory capacity
Form Factor Pico-ITX (10 layer) 10 cm x 7.2 cm

http://www.mini-itx.com/reviews/pico-itx/images/pico-itx-0025m.jpg (http://www.mini-itx.com/reviews/pico-itx/default.asp?page=1)

Again, click on the image to go to the retailer.

CrazyB

[widefault]

The common options...
Mini-ITX, 17cm x 17cm - Available for most CPUs
Nano-ITX, 12cm x 12cm - Only Via CPUs
Pico-ITX, 10x7.2cm - Only Via CPUs

The not-so-common options, from the embedded PC world
EBX, 5.25" Embedded, 203mm x 146mm - Most Via and Intel desktop and mobile CPU options
EPIC, 165mm x 114mm - Via and mobile Intel CPUs, some AMD Geode LX models as well
ECX, 3.5" embedded, 146mm x 104mm - Pretty much the same CPU options as Epic
PC/104, 96mm x 114mm - Low power CPUs are most common(Pentium/386/486 class), some Via and Geode models out there.

They all get more expensive as you get smaller and/or faster, especially in the embedded boards. Now, you can get used boards on ebay every so often for a significant discount, but you often don't get the cables and other specialty parts embedded boards often need.

Unless you have an open budget, you'll have to compromise between size, performance, and price.

[Mach]

Check out is wired article for examples of SFF and TFF computers

http://www.wired.com/gadgets/pcs/multimedia/2007/07/gallery_tiny_pcs?slide=1&slideView=3

http://www.gumstix.com/index.html