Intel Corp (INTC)

[Elmer Phud]

Mr Chin -

I see you scolded by Admin for being nasty boy. You be good now and I let you speak to me.

I see you're confused still. Not surprising. I didn't say PCI-Express has a 250MHz clock so don't put words in my mouth. I fact I said nothing about a clock because there isn't any. I was trying to be generous and help you understand but you were too bitter to understand help when you need it.

The PCI-Express bit rate is 2.5Gbps. It is 8b10 encoded so the "clock" can be derived from the data if you wish, but why bother?. (See how I was trying to help you?) As each byte appears a 10 bits, a 250MHz clock would operate the logic that does the 8b10b encoding/decoding. How the bit stream is sampled/generated to ensure correct data at 2.5Gbps is a problem the designers must address and I don't think it needs to be part of the spec. I would explain it to you but that is proprietary and besides, you wouldn't comprehend. How it is tested is just as secret and even more incomprehendable to technicians. I hope this little lesson helps you understand a little about the "clock".

Now be polite and respectful and I will help you again next time you are in over your head.

EP