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According to me stranded wire is good for carrying power(e.g. Vcc) but for carrying signal(e.g. 100MHz I2C traffic) I feel they create noise & since different strands might have some phase difference between them & since they are so close touching might put some noise in other strands. Also, the position of strands relative to each other can change over time with movement & handling. Solid wire seems to be better for carrying signal to me. I think I need some expert advice.

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    \$\begingroup\$ I2C is 100 khz, 400 khz and 1 mhz standard. Not 100 MHz \$\endgroup\$ – Passerby Nov 15 '15 at 3:15
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For short distances (e.g. < 0.1 m), stranded or not makes little difference for signals between ICs. I2C is not 100 MHz - max 2 MHz or so. In these cases, the greatest loss is from parasitic capacitance.

Strands touching or not makes no practical difference -- signals between ICs have enough noise margin to make any difference imperceptible.

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you can expect a 3mm difference in strand length to distort edges at around 10ps.

On a single sided, or double sided circuit board you're un likely to be dealing with 10 picosecond edges. (thats like 50Ghz)

Use whichever style of wire is most convenient.

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  • \$\begingroup\$ Probably closer to 15ps, but who's counting ;) \$\endgroup\$ – Tom Carpenter Nov 15 '15 at 3:51
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    \$\begingroup\$ "ps" means picoseconds. \$\endgroup\$ – Jasen Nov 15 '15 at 3:59
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    \$\begingroup\$ @Passerby the propagation speed of high frequency signals in cables is on the order of 50% to 70% of the speed of light (depending on the cable). So it is roughly 5ns/m velocity. \$\endgroup\$ – Tom Carpenter Nov 15 '15 at 16:29

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