Chaos zakum/horntail

I haven't been on any zakum runs lately so I don't know about that, but I have dced on every single Horntail since my old Marksman got deleted (before Evan patch) as soon as body is summoned and I've been having strange half a second lag spikes every few seconds, and it's annoying as pineapple. I've tried messing around with graphics, etc etc, doesn't work. I also dc at Nibelung, I assume it's the same issue.
The laptop I play on is several years old so I'm getting a new one soon. It's going to be windows 7 OS though, and all this negative feedback about windows 7 + maple is making me nervous...