1 box upgrade or go with 2 boxes?

I currently can play 4 accounts fairly smoothly on my main comp. However, in SW for example, 4 accounts are almost unplayable. huge software lag causing follow to almost never work. When I go up to 5 accounts, I can still play decent with occasional software lag, but no hope at all of going near cities. I would like to 5 box and be able to move through cities as a group. I have a 2nd box that I was considering running 2 accounts on and doing 3 on my main comp, but I would prefer to keep them on one box if I could for the 5 box pip switching. I'm also concerned about screen layout b/c I only have 1 screen atm. I am ready to upgrade my main box if it would cleanly do 5 accounts in cities. Tell me what you think of my 2 system's capabilities and my proposed upgrade.

Box 1:
AMD 64 x2 5000+ brisbane (65 nm)
2g ballistic tracer
nvidia 6800gt

upgrade box 1 with:
2g more ballistic tracer (4g total)
nvidia 8800gt

or use Box 2:
amd 64 3800+
1g ram
radeon x1650pro

either way, I'm going to be purchasing a 22 wide to use for main. do you think the upgraded box 1 could handle 5 boxes cleanly? Do you think as is box 1 and box 2 can cleanly handle 3 and 2 accounts cleanly?


Edit: the tracer is ddr2 1066 and the cpu is black edition. Decent cooling setup. I would feel comfortable with a bump in FSB speed and clock the cpu up to the 2.8-3.0 region if that would solve my problems as well in either situation.

I'm no expert, but i'd say go with the 2.

Update: After some tinkering, I am currently running cool and stable with a FSB of 210 and multiplier of 14 with no voltage increases. This brings my clock speed to 2.94 ghz and memory clock to 840 mhz. I also was able to overclock my video card enough to ensure myself that memory is my main bottleneck. I'm going to be going ahead with purchasing 2 gig more of ram and upgrading my video card to a 8800GT. I'll update again with the specific performance that I can garnish from this system when the parts come in.