The more questions we get, the more we think that no one has all the answers - but your question is pretty reasonable. There are two approaches you can take: roasting in a moderate oven or slow-roasting at a lower temperature. Either way, with such a large roast, it's going to take quite a while to cook. The National Cattlemen's Beef Association would have you roast it at 325°F (160°C) for about 4-1/2 to 5 hours, until it reaches an internal temperature of 150°F (65°C). They want you to loosely tent the roast with aluminum foil after about 3 hours, to keep the outside from drying out. Let the roast rest on a cutting board for 20 minutes after it comes out of the oven, and the temperature will rise to 160°F (71°C), or medium well done.

The more trendy slow-roast method is an effort to allow the meat to cook through to the center without overcooking the outer portions. It is a little more work and a little less precise. In this method, you would first brown the meat in some oil in a large Dutch oven on the top of the stove. Then pop it in the oven at 250°F (120°C) for hour after hour - probably 6 to 7 hours. When the internal temperature reaches 130°F (55°C), boost the oven temperature to 500°F (260°C) and continue roasting until the internal temperature reaches 150°F, about 30 minutes. As with any method, let the roast rest in a foil tent for 20 minutes before carving.

The great problem with your question, of course, is that ovens vary, the shape of roasts varies somewhat, and people can't even agree on what internal temperature constitutes medium well done. So - and here's our advertisement for the day - it would be worthwhile to invest in an instant-read thermometer. Using one will take the guesswork out of cooking your roast.