Digital video recorder with slot type mainboard

1. A digital video recorder comprising:

a plurality of male slots;

a main board for supporting the plurality of male slots;

an image compression substrate connected to a first one of the plurality of male slots, the image compression substrate being adapted to accommodate a plurality of image channels and support a high-speed data bus dedicated for an image; and

a function expansion substrate connected to a second one of the plurality of male slots, the function expansion substrate being adapted to support a PCI type device,

wherein the function expansion substrate and the image compression substrate use separate buses, thereby improving system performance and speed.

2. The digital video recorder of claim 1 , wherein the plurality of male slots includes slots of PCI type and the PCI type device supported by the function expansion substrate includes at least one of a USB device and an IEEE 1394 device.

3. The digital video recorder of claim 1 , further including a connector to connect the image compression substrate with the first one of the plurality of male slots, wherein the connector connects to one side of a lower part of the image compression substrate.

4. The digital video recorder of claim 3 , wherein the one side of the lower part of the image compression substrate includes a female connector that is arranged on a surface of the image compression substrate and that is substantially perpendicular to a digital video recorder mainboard surface that holds the plurality of male slots.

5. The digital video recorder of claim 1 , wherein the image compression substrate is adapted to accommodate at least four image channels.