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Nomad
19-05-2010, 04:52 PM
Hi,

I was told that wireless might actually work at 10 or 20% of its stated speed on the device or its fancy cardboard box.

Anyone done testing?

I haven' tested many diff files.
That I think would work even slower.

For a one large 50MB file it was going at 1.85MB/sec. Not sure how this translate to 54 Wireless G Speed.



Cheers.

utopian201
19-05-2010, 05:20 PM
If i remember correctly, G speeds are about 20-30mbit/s, N is about 50-70mbits

Speeds drop drastically if you mix devices, so it is best to have an all G or all N network for best performance

1.85mb/s is about 15mbit/s. Were you transferring wireless client to wireless client?

Nomad
19-05-2010, 05:30 PM
Yup PC to laptop - shared HDD copying 1 file. Upstairs to downstairs directly underneath. Both G via a router.

trinsic
19-05-2010, 05:49 PM
I could get about 3.5MB/s on mine.

Once you bring USB and overhead into the mix it is quite slow.

Chilling_Silence
19-05-2010, 06:31 PM
Bear in mind that 3.5MB is 28m/bit ...

utopian201
19-05-2010, 06:39 PM
Yup PC to laptop - shared HDD copying 1 file. Upstairs to downstairs directly underneath. Both G via a router.

Your speeds sound about right then; wireless bandwidth is shared between all clients. So 15mbits x 2 = ~30 mbits which is about right for G.

Nomad
22-05-2010, 12:00 AM
I connected my old laptop to my router - 100Mbps. I got 50Mbps copying the same file. I double checked by by grabbing a 500MB single file - the same. So what's this thing about a 100Mbps, is 50Mbps sound about right?

What do people get with a Giganet?

My DVD drive provides 40Mbps. Reading and writing to the HD.

Nomad
22-05-2010, 10:15 AM
Well it seems maybe the old laptop has a limited bus and a 5400rpm HDD :waughh:

Would like to know if any have tested speeds using one large file - PC to PC (not laptops) with a standard SATA HDD (not RAID 0).

Maybe the mobile devices could transfer much higher with S Korea's 1000Mbps Internet cos they use static HDs.

Chilling_Silence
22-05-2010, 11:12 AM
I'm not entirely sure I follow what you've done ...
You do also realize there is 8 bits in a byte, and you need to make sure that you're comparing bits with bits, and bytes with bytes. 40m/bit per sec = 5m/byte per-sec.

Even older slower HDD's are generally capable of sustaining that kind of throughput

Nomad
22-05-2010, 11:28 AM
I copied a 50MB and a 500MB file (separate occasions) from Win7 PC to win2k older laptop via my router thru a wired connection (100Mbps).

The speed was avg at ~6.9MB/sec (under Win7 - show details) - times 8 = 50Mbps.

I copied a similar file from my DVDRW to the HD on the PC itself (not via network) and that gave 40Mbps. ~4.9MB/sec stated by Win7.

I'm gonna copy a file from 1 physical SATA to the other and see what speed I get :)

Nomad
22-05-2010, 03:00 PM
SATA to another gave 68MB/sec ~550Mbps. In the box, not via network.
Hmm....

Dunno what the issue with the backlog is, will redo, maybe a network has inefficiencies but that sounds excessive.

Chilling_Silence
22-05-2010, 05:26 PM
You'd be surprised at how poorly some NIC's actually operate

Nomad
22-05-2010, 05:37 PM
Love to know what some peopel get with a 100 or a 1000 setup.

Well .. dunno. PC is a Asus motherboard Aheros (sp?) freebie NIC. Laptop is a 3Com 10/100 Mini PCI :D

Well not complaining cos 55Mbps is sure plenty. Heck, 15-20 is good enof for wireless whcih is used 98%.

ubergeek85
22-05-2010, 08:10 PM
Aheros (sp?)

Do you mean Atheros?

Nomad
23-05-2010, 12:22 AM
Do you mean Atheros?

Yup.

utopian201
24-05-2010, 11:48 AM
My 100mbps when transferring large files (a couple of gigs) is about 7-8.9MB/s, that is about 75mbps.

The speeds as others have mentioned, depend on your NIC chip. Gigabit ethernet can go anywhere between 286-870mbps. The large range is due to tcp packet and window sizes.

More here
http://www.codinghorror.com/blog/2005/07/gigabit-ethernet-and-back-of-the-envelope-calculations.html

Gobe1
24-05-2010, 12:25 PM
•10baseT = 1 megabyte/sec
•100baseT = 10 megabytes/sec
•1000baseT = 30 megabytes/sec

thats about what i have been getting too when transferring large files only to my backup server