[fifty2aces]

I wouldn't bother with RAID - more trouble than it's worth, and not really relevant to trading anyway, since you aren't likely to be doing anything which requires heavy disk usage. As for graphics, while you need at least a decent card, trading isn't graphics intensive compared to gaming (high-end graphics are designed for 3D performance, rather than a bunch of charts). SLI is considered excessive by many gamers, so is definitely unnecessary - it will only help for multithreaded graphics, which won't be an issue for trading.

If you downgrade the graphics, and stick to 1 hard disk (no RAID), you'll get a cheaper computer, which will probably have much better battery life, without impacting performance. You could even look to get a faster processor, which will be far more useful than SLI or RAID.

Edit: Also, custom trading computers are pretty unnecessary - generally the ones I have seen use standard parts, but market towards insecure traders who are afraid that their computer might hold them back from getting that extra tick. The only time a custom job might be useful would be if you needed more than 2 monitors, in which case motherboard and graphics card selection is important, and most off the shelf computers won't do the job.