Presumably the different computers you mention are in different rooms:
You should try to optimise reception and avoid interference to the problem computer.
1) raise the router above furniture level
2) Experiment with channels (some will work better or worse depending on your environment)
3) If you can detect strong neighbouring wifi, use a channel 5 stops away from strongest.
4) Relocate cordless phone base or video sender etc.
5) Be prepared to move the computer (or at least turn it so your body is not between the router signal and the wireless adapter's antenna.
alright so here is my setup, first we have our modem, which is connected to a wired linksys router (which needs to be there for our slingbox and tivo), then off of that we have a wireless netgear router mentioned above.
1-the router is about 3 feet off the ground and can't really be moved because it's attached to our tivo and slingbox
2-Tried every channel, 1-11 and i get 2, maybe 3 for a little while
3-there are no other wireless signals being recieved
4-no cordless phones near my computer
5- I have the adapter attached to a USB cable so I can angle it around, and even then I don't have much luck, and i can't move the computer to a different spot outside my room.
The annoying thing is that my macbook and HP laptop both get full bars in my room, and I can play games on them without lagging like I do on my desktop with this adapter.
Hang on where did I get the idea that the router was a Linksys. Ignore that.
Both pieces of equipment are Netgear and both are wireless n not g (aren't they ?).
I don't use n equipment so I can only suggest you download the full manual for the router and read it. I suspect that you've set the router's wireless to mixed mode because you think the adapter is wireless g -- if it's not you will compromise the performance.
Internal cards can draw more power and I think that's why they work better.
The problem comes with the computer location and with PCI (unlike USB) you can't extend the antenna without signal loss.
I have no wife to bitch about how the room looks and have my computer jammed against the wall nearest the router (which is 40 feet away and down one floor) and because I don't game or torrent or whatever I can put up with a 50% signal.
You've tried USB and it wasn't great -- I'd consider PCI-E but be prepared to move the computer around because there may be special problem in the room your in (such as metal beams, foil wall insulation).
well it's worth a shot I guess. It's just kind of ironic how my laptop which chugs while playing COD 4 on lowest settings can get a better signal than my enormous desktop that puts damn near everything to shame.
too bad I couldn't just get LAN ports everywhere in my house
the WNDA 3100 is not the most recommended adapters it's got its own share of woes ...being a dual band adapter and an eye candy it's a marketing face of NG and nothing more...if possible replace WNDA 3100 with WPN 111 which is a pre-n standard the same as ur router as its far better than wnda...if u want to use the same USB adapter for a mac i'd suggest WG111v3 or WN111v2 which have respective drivers...