It's possible to drastically improve your client performance by reducing some of the graphical settings available in the game. Before getting into a fight consider reducing things like the particle slider, view distance, and disable shadows (under graphics and terrain settings).
If you're fighting in an area with a lot of vegetation, reducing the draw distance for non-colidable flora and nearby radial flora can also help performance (under terrain settings). In a large fight, change the chat setting on the combat message filter to 'self'. This will reduce the amount of messages. In large fights, having the combat tab show all messages can cause a serious performance impact.
Try not to take part in any battles larger than 16 on 16. This will drastically reduce the amount of stutter you experience during battles. Ask your friends and opponents to turn down their settings as well so you can experience the best possible action!
Where to Find the Action
There tend to be several focal points for PvP, the largest of which is the ruins of Restuss.
To get there, simply hop on a shuttle to Restuss Starport near Rori. From the landing area you'll be able to make out the edge of the ruined town. In order to approach the ruins you will have to be flagged as 'special forces'.
Aside from Restuss there are three smaller battlefields. One on Naboo, another on Corellia and the last one on Talus. If you can take and hold one of the bases, the factional officer in the base will offer increasingly useful rewards such as healing stims, damage shields and items that will let you regain action on the fly.
There are a lot of ways to get around the galaxy. While most of the common fighting spots will have a shuttle destination, allowing for easy transport, don't underestimate the benefit of items such as an ITV that allows you to travel to a local destination without having to catch a shuttle or use a space ship. If, for example, the enemies are controlling the entrance to Restuss, look at your planetary map. There might be a second shuttle near the city that would allow you to easily approach the ruins from a different direction.
Camps with shuttle beacons and cloning facilities can be very useful. This is especially true when fighting away from starports and cloning centers. Making good use of camps can allow you and your group to quickly get to the action and quickly recover after being forced to clone.
A note on vehicles: Remember while PvPing, your vehicle becomes as much of a target as you do. Don't ride what you are not ready to see damaged.
Using a rare and hard to repair vehicle can result in an unexpected ambush, which would lead to a hefty repair bill. For insurance, you should consider buying a couple of regular swoop speeders off the local Bazaar Terminal. If they get shot up you'll only be out a small amount of credits.
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