Wireless N getting only 30 Mbps on file copies

[michaeljc70]

I was getting 30 Mbps copying files from my main PC which has a wireless N card and my media PC which is wired into the router (Netgear nr2000). It seemed to take forever copying large files.

I upgraded to a Cisco e3000 dual simultaneous band router thinking that would help. I am getting the same speed. I have both bands set to use wireless N devices only.

Is this a normal speed? Is there anything I can do to tweak my network to make it faster?

BTW, I used LanSpeedTest app to test the speed which just copies a file I guess.

 

[PhilFrisbie]

File copy speed is not only limited by the network connection speed, but also by the hard drive read and write speeds.

 

[michaeljc70]

Yes, but a network is almost always faster than a hard drive. When I do the copy using lanspeedtest on the same machine, I get 5500Mbps.

 

[PhilFrisbie]

Yes, but a network is almost always faster than a hard drive.

?? That is exactly the point I was trying to make. The copy is likely being slowed by one or both of the hard drives. . .

 

[PhilFrisbie]

When I do the copy using lanspeedtest on the same machine, I get 5500Mbps.

Hmm, 5500Mbps? Wireless N has a top speed of 300Mbps. . .

 

[michaeljc70]

Hmm, 5500Mbps? Wireless N has a top speed of 300Mbps. . .

As I said- "on the same machine" meaning no network was involved. The point being it is not a hard drive limiting the speed as it can copy at 5500Mbps if you remove the network aspect of it. It is the network and that is why I posted under wireless networking.

A hard drive (unless it is truly ancient) is always faster than a wireless network.

 

[PhilFrisbie]

As I said- "on the same machine" meaning no network was involved. The point being it is not a hard drive limiting the speed as it can copy at 5500Mbps if you remove the network aspect of it. It is the network and that is why I posted under wireless networking.

A hard drive (unless it is truly ancient) is always faster than a wireless network.

OK, you got me there; I did not see "on the same machine", but 5500Mbps is still a bogus rating. SATA 3.0 is rated at 6Gbps (6000Mbps), and unless you have raided SSDs or high RPM hard drives you cannot sustain close to 6Gbps reads/writes.

Also, you must not have seen the ratings on current low power laptop drives. Many of those cannot keep up with a basic Wireless G connection. . .

 

[michaeljc70]

I'm not really here to argue about hard drive speeds on the wireless networking forum. The point is my N router and receiver are rated for 300Mbps, my drive is 6Gbps and I am getting 30 Mbps. I know those are rated speeds and it isn't really that fast and there is overhead, etc., but it seems I should be able to get 1/2 or 1/4 of the rated speed and not 10% of it.

 

[PhilFrisbie]

I'm not really here to argue about hard drive speeds on the wireless networking forum. The point is my N router and receiver are rated for 300Mbps, my drive is 6Gbps and I am getting 30 Mbps. I know those are rated speeds and it isn't really that fast and there is overhead, etc., but it seems I should be able to get 1/2 or 1/4 of the rated speed and not 10% of it.

I agree with everything you said above, but you left out some critical information: what is the speed of the hard drive in your media PC, how fast is the connection between it and the router, and how fast is the connection between you PC and the router? Don't say the wireless connections are 300Mbps unless they are VERY close to the router, and the wireless adapters are capable of 300Mbps and not just 150Mbps.

 

[michaeljc70]

The wireless connection is about 20 feet from the router. It is capable of 300Mbps according to the documentation and when you view the adapters properties. It shows I have all bars for the wireless connection.

The wired PC is connected via Gigabit.

Both hard drives are Seagate Baracuda 7200 rpm drives. It looks like the drives may be rated at 3Gbps, not 6.

I already have them both set to accept wireless N connections only. I am wondering if I should use the 5Ghz band only. I am not sure how to tell which I am connected on. They both have the same SSID. I suppose I could give them different SSIDs and connect and test the speeds and see if that makes a difference.

 

[PhilFrisbie]

I already have them both set to accept wireless N connections only. I am wondering if I should use the 5Ghz band only. I am not sure how to tell which I am connected on. They both have the same SSID. I suppose I could give them different SSIDs and connect and test the speeds and see if that makes a difference.

I am going to need to defer to others; While I have an N router, none of my wireless devices yet support it, so I have no experience with restricting bands.

Good luck!

 

[pacifist86]

Just to provide a little clarification, you are looking at apples and oranges when you compare the maximum throughput rating of a wireless n device to the transfer speed achieved during an actual file copy.

Mb/s or Mbps means megabits per second. To convert to megabytes (MB/s or MBps), you simply divide by 8, since there are 8 bits in a byte.

So 54Mb/s = 54Mb/s * 1Mb/8MB = 6.75MB/s (802.11g)
And 300Mbps = 300Mbps * 1Mb/8MB = 37.5 MB per second (802.11n)

So you can theoretically cap out just under 38 MB per second.

Here is a similar discussion regarding this on wireless-g routers. (link)

Here is an article that talks about a few things you can tweak on a router that may improve performance. (link)

 

[michaeljc70]

I understand that. LAN Speed test reports speed in Mbps which is the same as the speed routers/adapters are rated. Since I am getting 30Mbps, I am getting about 10%-15% of the theoretical max. I looked at the site with tweaks, along with some posts specific to my router, but didn't really get any increase. I also tried another wireless n adapter.

 

[michaeljc70]

After playing around, I've discovered 1) my N adapter is only capable of 150Mbps and 2) the adapter will only connect to the 2.4GHZ band. If I turn off the 2.4GHZ band, it doesn't even see the network.

Basically, that is limiting me to 65Mbps, which 30Mbps is probably the real world speed of that.

I still don't know why I cannot connect any faster than 65Mpbs though. Do I need a dual band adapter to connect to the 5.4Ghz band?

 

[jansoris]

Holy *** there were a lot of morons in this thread that didn't understand that laptop hard drives can read/write faster than 2.5 MB/sec (yes, mega byte -- since the other guy felt the need to enlighten us that there are 8 bits in a byte... thanks, what a life saver, never heard that before )