"END OF LIFE" stages. But back to your new router. Since the old routers can't penetrate that floor I doubt much else will.
Let's start with the usuals.
1. Set it up our way (see forum sticky)
2. Consider powerline bridges to put another wifi router or wap on the next floor.
I installed this router 2 days ago. Before it we used 3 different b series routers --a belkin, a linksys and a motorola--none of the 3 would reach our downstairs room--we have dsl on a Paradyne modem from our phone company--the 824 will kind of reach the lower floor with a weak signal--our house has sheetrock and wooden walls and floor-I amvery inexperienced at this and after I installed the router the first desktop a very old Dell p3 with a D-link usb adapter started instantly but won't hold a connection very long--Mine is a slow homemade p4 direct wired to the router and stays at 100mbps constantly and never loses connection--the third is a dell 4600 p4 with a dell old flat adapter wired to a usb port--it would show it knew the network was on but would not aquire the number it needed to join the network--my son-in-law who is a network adm with a large wired network at a utility co came over and killed the security temporarily and we got this computer and the one downstairs (another dell 4600 witha linksys adapter) to join the network--he says to get wireless pci card with a wired antenna for downstairs and use the linksys adapter upstairs and we shouild be able to get the security back on--BUT all the wireless connections constantly go up and down on speed and power like from 11 to 50 on speed and the one cloest to the router(about 20ft.) loses its connection every few minutes and it worked great but slowly on the old router and the next 4600 at least worked slowly and kept its internet connection--will the pci card help downstairs and why does everything go up and down constantly?