2 memory questions

[cpujunky]

1) What is 4-way interleave or whatever? Whats the advantage and what has to support it?
2) I was reading one of Tom's Video Card reviews and it said that the VC memory was 5ns so it would overclock to 200mhz at most. Is there a relationship between access time and bus speed?

 

[phsstpok]

I can't explain how memory works but the numbers are reciprocals of one another.

The 5 ns refresh rate can be expressed as 5 nanoseconds/cycle which means 0.000000005 second/cycle.

The frequency of 200 mhz can be expressed as 200 million cycles/second, or 200,000,000 cycles/second.

200,000,000 cycles/second multiplied by 0.000000005 second/cycle = 1, exactly. Hence, reciprocals.

Similarly, 6 ns relates to 167 mhz (rounded), 7 ns relates to 143 mhz, and 7.5 ns relates to 133 mhz.

 

[snn47]

I am looking also for an understanding and I found a lot at lostcircuits, while not complete at least a lot more wisedom then here.