FFXI developed stuttering issues

[Absolutely Virtue]

I have a weird problem, and it doesn't seem to be addressed in the other threads (or anywhere else on the internet). But I figure it has to be something simple, and I'm just too stupid to figure it out.

I have a Toshiba laptop I bought about six months ago for work, and it used to play FFXI fine. In fact, the specs are good enough that I was able to run FFXIV on the default system.

But I took a break from FFXI in the fall, and in the interim something bad happened. Now the game has developed a stuttering issue that makes it unplayable. It will log into POL just fine, but starting with the FFXI title screen, and in every in-game location (crowded areas, remote areas, etc) it has a constant, consistent stutter. About every half-second the game will freeze for a quarter-second, almost like you're watching it frame-by-frame. It ticks like clockwork, and I can't do anything to remove it.

The following things have changed:

1) I got a new modem and router (I moved). I don't experience any other connection issues on any other devices on my network.

2) FFXI has obviously been through a number of updates, including big version updates.

3) The machine came loaded with a ton of bloatware, most of which I have removed. But it's always updating shit, so who knows what could have changed.

Unfortunately, since I was away from the game for a long time I can't pin down exactly when the problem developed. I'm of course inclined to believe it has something to do with the modem, but I'm not savvy enough to figure out what it is. What seems to make my problem unique from what so many other Windows 7 people experienced is that at one point everything worked fine.

I have tried:

1) Bypassing the router and connecting directly to the modem- no luck
2) Completely un-installing and re-installing from a brand new compilation disc- no luck
3) Running with windower, w/o windower, at different display settings- no luck
4) Updating latest video drivers, and rolling back to previous versions of the drivers- no luck

Probably the modem, right? What should I do to confirm? Unfortunately I don't have the old modem anymore. For the record, my ISP is Comcast, I have an Nvidia Geforce 330M, I'm running Windows 7, and my a/s/l is 35/M/Washington, DC.

Please tell me I'm stupid and it's something I can fix easily. Thank you. I love you.

[sruon]

Windows Registry, fragmented HDD, bloatware polling the CPU every few seconds... hard to tell

Formating and installing a clean official Windows 7 ISO is your best shot.

[Absolutely Virtue]

Thanks for the quick response.

I had assumed that since the problem is isolated to FFXI, it might not be something as drastic. The format/re-install is going to void my warranty, right? Need to be careful about that since I use it for work and it was awfully expensive.

[sruon]

Shouldn't, you probably have a sticker under the laptop with your Windows 7 key.

You could always try cleaning the computer with Malware Bytes, CCleaner and Spybot S&D