Seventeen or Bust/Sieving
The recommended program to download is Proth_sieve by Michael Klasson and Paul Jobling. The client has not been optimized for SSE2 yet, so any P4 is better at PRPing and Factoring. For those who demand a GUI the client of choice is SoBSieve 1.34 by Paul Jobling. Be warned, though, that this client is 40% slower than proth_sieve. For operating systems other than Windows and Linux, NbeGone is the client of choice. Check out the different supported systems in his home page.
You'll also need an UPDATED sob.dat. You should (better, you must) use the high-n dat, more chances of finding factors, and the completed ranges will never be done again to check for high-n factors. (the downloading link is at the bottom of the second post; Ctrl-F for 991-50M dat) Place the dat in the same directory as proth_sieve.
Reserving a range
Recent reservations are made through the sieve coordinator. Just register and click to reserve a range. Choose the size of range that fits you best, choose the first value available (around 991000).
Working on the range
Turn proth_sieve on. Input your starting number and the ending one. Just wait after that until it finishes.
Go to the sieve coordinator and mark the range as completed. After that, look for a file called fact.txt and copy all of its contents. Place them in the box [www.seventeenorbust.com/sieve here](make sure you're logged in to receive credit for your work)