Hi when i install a graphics card, namely the nvidia 9500+ or the latest one the geforce fx 5500 my wireless connection ( the pci card ) loses all connection, sometimes it comes on then for a short while then it goes all together, tried uninstalling wireless then installing after graphics to no avail, when i take out graphics card there is no probs, any idea's before i buy a new pc. ( wife not happy as this emachines 5450 is only 18mths old )

hate to break the bad news, but emachines are absolute crap and known for poor quality. Their PSUs are typically underpowered and the components are of the cheapest quality. My suggestion is to replace the PSU.

I've ran an fx5200 with 2 HD's, a baton 3000+, 2 optical drives and 2 sticks of ram all on a bestec 250 watt which I think it also the same power supplies HP uses as Emachines