CAT5e or CAT6e cable?

[#1]

Would changing from CAT5e to CAT6e cabling have any effect on my network performance on a 1Gb ethernet connection?
I'm currently transfering files at about 38Mb/Sec over CAT5e between my computer and a Netgear NAS with a Netgear DGND3700v1 router in the middle.

[#2]

It's highly likely that it's not network saturation but disk saturation you're experiencing.
How many disks are there in the array that you're writing to?  What sort of RAID level?  Are they spinning rust or SSD?  Does it have a hardware RAID controller or a software/BIOS level RAID?
Max (theoretical) peak transfer rate on gigabit is 125MB/s.  In practice, even 50% utilisation (62.5MB/s) between two devices is considered "pretty damn good" in a networked environment.  Saturation of a gigabit pipe is usually only possible with many clients connecting to a single host.

[#3]

Try LAN Speed Test Lite (totusoft.com) for a speed test between your PCs.
Even basic things like more up-to-date network card drivers make a big difference in transfer speeds - but you are ultimately governed by your hard drives.

[#4]

I'm inclined to agree that it's disks rather than network.
There are two disks in the NAS in X-RAID2 configuration. They are both 2TB Western Digital SATA3 disks. The NAS is a ReadyNas Duo (ARM version).
Was just needing to get some new cabling so thought I would get CAT6 if there was any benefit to it.

[#5]

At the enterprise level, I use a "20MB/s" rule of thumb for ballpark sustained write speed per spindle - this pretty much extrapolates up to massive disk arrays like the ones we use.
Based on that, your 38MB/s seems to be pretty much spot on for a 2-disk system.
In which case, improving the cabling will do absolutely nothing to increase those write speeds.
B.

[#6]

Quote from: kingkobra

Would changing from CAT5e to CAT6e cabling have any effect on my network performance on a 1Gb ethernet connection?

Absolutely none.
Unless your cable is faulty and it's not actually running at 1Gb, or is giving an extremely high error rate. 

[#7]

I would try updating all your drivers and firmware for the ReadyNAS/router.
Then try one of the hard disk utilities to measure speeds. I have the same HDs (in Raid 1), but get twice your speed.

[#8]

I was also wondering if a proper switch alongside the router would have any effect, but these replies suggest any difference would be minimal.

[#9]

Try connecting your Ready NAS directly to your PC - you might need to set up static IPs as you are taking out your DHCP server.
This should give you an idea of your max transfer rate.

[#10]

Are you using your router to connect all your devices?
Most routers don't have gigabit ports so addind a gigabit switch may help.

[#11]

Quote from: philwilcox

Most routers don't have gigabit ports

See post #1