I saw a 4-port card for sale somewhere that did that. It was basically just 4 cards in one, but worked parallel. Needless to say, it took four ports on the hub/switch/router. But that's some pretty decent bandwidth.
You could always get a gigabit network card for $70. The hubs/switches/routers are rather expensive, is the only problem.
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well... I think it depends on what cards you use. I don't think they have it for stuff other than on board (my tyan Thunder K8S has 2x broadcom gigabit onboard and there is something on the driver CD that do this kind of thing... never manage to get to it due to the limited number of ports on the router/switch I have [besides the fact that other computer is still 10/100])
cards that have only one port are not expect to be bought for that purpose, so I don't think they'll implement that feature.
Yes, it's called Teaming but the cards must support it and must be identical. Also, plain Windows can't do it. I have twin NIC's in several of my servers at work, "old" Compaq DL380's, but they also have 15K rpm drives that hot swap and run Windows 2000 Advanced Server. Gets us 200Mbps from two cards, with a failover mode. But it's hard to find a consumer grade NIC that can do this, and I pretty sure it must be a server OS plus the teaming software.
Ok, so the whole idea is to try and triple your network throughput at lan events. I wish it was so simple but,
1. if you have a gigabit card on a desktop system you are already hitting the limitations of your hard drives and bus. Unless of course you have some 15k scsi drives..connected to a pci-x bus.
2. Teaming networking cards need driver support from the manufacturer and also the switch has to be configured as well.
3. For lan events, I'm assumeing gameing is the main thing here so wouldn't you want lower latency instead of higher throughput? Unless you tradeing huge files as well, and now we are right back to item 1.
If running Linux for the server is an option, there's no need to have matched cards and special drivers form the manufacturer, just set up good ol'-fashioned bonding. Pretty damn easy and pretty effective.
Only requirements are multiple supported network cards (you have to try really really hard to get a card that's not supported by Linux), multiple separate ISP connections (won't be an improvement if you just split the connection with a switch/router then just recombine), and a Linux distro that either has bonding support already or the ability to rebuild the kernel/add modules.
If interested, here's a howto specific to debian, but the ideas are the same for any distro.
I don't think the switch necessarily needs to "support" the teaming feature. In Mac OS X Server 10.4, the OS natively supports this feature, called Link Aggregation. If 1 OS (Unix based) can support this feature without needing any switch configuration, as it is handled by the OS (some form of load balancing across the network ports) then I don't think windows should need to have any switch configuration either...unless MS simply doesn't know how to handle this sort of thing...
Let's say, for example, that you are wanting to do this at home. Most people have only one ISP.
In that case, you could hook up as many cards as you want, but your speed is capped at the single ISP connection. That means that you won't break the 1.5 mbps ISP connection no matter how many cards you have.
Now, if you do this at a LAN party, then you might see an improvement. I have nVidia NIC's (2) on my motherboard, and I get great performance. But I also have two ISP's - one cable and one DSL.