Can I make PS3's presence on network "less intrusive"?

the phrase "every computer on my network" is a dead giveaway here. If you've got enough computers on your network to be using that verbiage, you are bound to get some heavy bandwidth traffic no matter how good your connection is.

I bet if you leave the ps3 and all your pc's but one connected, and then reconnect the other pc, you'll see the same effect on your pc's and maybe the ps3 too. Any newly established connection will start at a high bandwidth level, then the data flow gets a bit more efficient and it drops down to a fairly consistent, low level. This is because connections requires a high level of data flow activity at first, after which the pc or ps3 can just sit there, and only has to periodically tell the network, "yeah, I'm still here."

This happens with all network connections, but with a router and a lot of connected pc's it is magnified. This is because the router's job is to take a limited amount of bandwidth, and ration it out as fairly as possible to every connected device. The router can't prevent the high flow of data that happens when a device first connects, though, so when your ps3 connects, it has to give the ps3 a big chunk of bandwidth. Because it has already limited the bandwidth of some of the other devices, this causes some of them to go from zero to none. It's like a government slashing its budget in a recession, the little programs that didn't get much money in the first place are terminated.

Once your ps3's connection is established, its bandwidth use naturally decreases and the router can step in and manage it. But not during the connection. If you restrict its bandwidth usage during connection, it often will fail to connect entirely. (try connecting to psn with a download running in the background for an example of that)

How to solve this problem? Only one way really, that is a better internet connection. The router has nothing to do with it, even the cheapest routers can handle 50Mbps of data flow which is 10 times the speed of a T1 line. If you're using a basic 256 up/256 down DSL line, you should upgrade to one that can handle at least 1.5 Mbits download, better yet 3 Mbits or 5 Mbits, and at least 896kbits upload.