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Fedorenko
9th June 2004, 05:32 PM
A quick question for all to consider. How many layers are there on the standard comptuer related PCB?

Byrd
9th June 2004, 07:00 PM
Hard to say.

The PCB layers on a modern motherboard can vary from 4 - 8 layers. As a general rule, the larger the motherboard is, the less layers it has. There are exceptions to this rule however - for example the VIA EPIA series of motherboards, measuring 170 x 170mm have just 4 layers.

Also, the greater number of layers a PCB has, the more expensive it becomes to produce. The Geforce 6800 has a 12 layer PCB, while the Radeon X800 has just 8, and hence is cheaper to produce.

JB

Fedorenko
9th June 2004, 07:20 PM
So, mabye 4 or 8 for a full blown mainboard eh?

Would the age of the mainboards make a difference (like, in the old days they used to use 8 layers isntead of 4)? As an example, how many layers would a PM 9500 board have.

Byrd
9th June 2004, 09:03 PM
The less complex the motherboard, the lesser the amount of PCB layers - PM 9500 might have about 4 - 6. A fast, current release motherboard requires 6 - 8 layers to shunt a huge amount of bandwidth around and to remain reliable without interference.

Have an 8Mhz XT motherboard lying around somewhere here - it's one layer, consisting of thick strands of solder between each IC :)

Fedorenko
10th June 2004, 05:21 AM
Now wouldnt it be simpler if they were all like that XT :P

Hmm, shall have to look into the specifics of certain systems later, for what I am doing, 4 layers would be the sweet spot.

Ahh, if only I could keep my computer related planning the same as most people. :D