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stormdragon
11-01-2009, 11:09 AM
Would there be any advantage in upgrading my home server from fast ethernet (integrated in the motherboard) to gigabit via a pci card or would the pci slot make it slower?

:thanks

Speedy Gonzales
11-01-2009, 11:13 AM
Unless everything else is gigabit, it wont make a diff.

stormdragon
11-01-2009, 11:27 AM
All other computers are gigabit capable, so if there would be an advantage I'd go and buy a gigabit card and switch.

Speedy Gonzales
11-01-2009, 11:41 AM
Oh well, in that case, it should be at gigabit speed. If all and the switch are gigabit. So, should be faster, for transferring files

stormdragon
11-01-2009, 11:48 AM
So you're saying that the pci bus wouldn't make to much of a difference?

Speedy Gonzales
11-01-2009, 11:53 AM
So you're saying that the pci bus wouldn't make to much of a difference?

Well it'll make a diff in speed. Since the onboard NIC isnt GB is it.

The card is. It shouldnt be slower. If it says its a GB card, it should give you GB speeds

SolMiester
11-01-2009, 12:59 PM
The pci bus is indeed slower, try pci-e...x1 or x4

stormdragon
11-01-2009, 01:14 PM
Thanks Sol that's what I expected sadly the board only has pci-e x16 and pci slots.

Agent_24
11-01-2009, 01:27 PM
Maximum speed is 1000Mbit, converted equals a maximum theoretical throughput of 125MB per second. the PCI Bus can transfer 133MB/s so this is within the limits. Of course, other factors will probably take your networks maximum speed lower than this, to about 80% of maximum or less

You can put a slower speed card (PCI-E 1x) into a PCI-E 16x slot

SolMiester
11-01-2009, 01:35 PM
Maximum speed is 1000Mbit, converted equals a maximum theoretical throughput of 125MB per second. the PCI Bus can transfer 133MB/s so this is within the limits. Of course, other factors will probably take your networks maximum speed lower than this, to about 80% of maximum or less

You can put a slower speed card (PCI-E 1x) into a PCI-E 16x slot

How are you calculating 1/4 speed?, you are correct in that hard` disc will also use the pci bus bandwidth but i dont follow your 25% step down??

tweak'e
11-01-2009, 02:02 PM
the problem with PCI bus is it very rarly runs at full speed. then also its shared with other cards and sometimes even onboard devices.
with gigabit lan and raid cards you can flood the PCI and cause problems.

Chilling_Silence
11-01-2009, 04:01 PM
That said, gigabit LAN is 125MB/s (divide by 8 to get bytes)
Peak transfer rate of PCI is 133MB/s or 266MB/s, however if the BUS is shared with other devices, it'll obviously affect speeds.
(http://en.wikipedia.org/wiki/PCI_Local_Bus#Conventional_hardware_specifications )

That said, I chucked a gigabit PCI Lan card into my desktop and got pretty darn good speeds during some ad-hoc testing. Transferred 5GB in around 3 minutes :)

Question is, for $20, do you really transfer that many large files to justify the outlay purchase of the LAN Card, as well as potentially cables and a gigabit switch?

Agent_24
12-01-2009, 11:36 AM
How are you calculating 1/4 speed?, you are correct in that hard` disc will also use the pci bus bandwidth but i dont follow your 25% step down??

I'm not sure where that 25% is coming from myself...


That said, gigabit LAN is 125MB/s (divide by 8 to get bytes)
Peak transfer rate of PCI is 133MB/s or 266MB/s, however if the BUS is shared with other devices, it'll obviously affect speeds.

This is what I meant, 125MB/s (if you're lucky to begin with) will not use the entire bandwidth of the PCI bus... this is ignoring other data transfers through it.

I find that my maximum throughput for my own LAN (this is on 100Mbit ethernet) is about 80% of the maximum it could be (should be 12.5MB/s, usually about 10MB/s peak, 8.5MB/s continuous) but then I have cheap switches :)

Which is another thing you have to watch out for - the cheaper ones also distribute the entire bandwidth through the entire device, so full speed transfer can only be obtained when only 2 computers are copying data. (It's 100Mbit shared between all ports, not 100Mbit dedicated to each port)

So for a 24-port switch to allow full 100Mbit speed through all ports concurrently it needs to have a 4.8Gbit "backbone" (for full duplex mode)

SolMiester
12-01-2009, 12:04 PM
I'm not sure where that 25% is coming from

Ummm, general bites\bytes miscomprehenion 101!?...:blush:

sroby
12-01-2009, 12:22 PM
Whats the SUSTAINED data throughput speed of the hard drives at both ends??

Chilling_Silence
12-01-2009, 02:50 PM
HDD speeds are generally MUCH faster than that

Grab the little app here, CHDDSPEED , and use it to test your HDDs transfer speeds :)
http://www.benchmarkhq.ru/english.html?/be_hdd.html

stormdragon
13-01-2009, 05:06 PM
Thanks for the feedback, think I might just leave it a while then upgrade the server to a dual core atom board with onboard gigabit lan.

:thanks