Bottlenecks for 100 vs Gigabit?

[Pandamonium]

I'm looking into replacing a server (well, at least giving the machine enough horsepower to do more than file and print serve) and am wondering if I should look into gigabit ethernet.

I'm planning on getting two high capacity (>=200GB, haven't decided what) 5400RPM disks to put in RAID 1, but would the disks still not be able to saturate a 10/100 network? If my network becomes the limiting factor, what kind of gain should I expect from moving to Gigabit ethernet? I've read that real world performance on Gigabit varies greatly - sometimes approaching that of 10/100....

If Gigabit will yield a significant improvement, can you recommend a motherboard with it and everything else integrated? (well, at least video)

 

[charlie21]

100 Mbps = 12.5 MB/s, which even a 5400 RPM disk can easily saturate. If you move to gigE, then the disks couldn't keep up.

 

[gunrunnerjohn]

FYI, there is more to the process than replacing the NICs. I have three machines equipped with Intel Pro/1000 MT gigabit adapters, all connected to a Edimax gigabit switch. Writing from a client to a "server" (really just a W2K machine), I only get a 20-30% speed boost over the 7mb/sec I get with 100mbit adapters. Reading from the "server" to the client, I get about 25mb/sec transfers, so I'm pretty sure that the bandwidth isn't the issue. This works the same, no matter which machine is the "client". I suspect the SMB overhead in writing on the remote machine, but I don't really know for sure.

I've beat this topic to death here before, and no answers were forthcoming... If you figure it out. PLEASE post your solution.