What temperature for a 3lb roast?

Rare: Cook the beef tenderloin to 130 degrees F, then remove from heat and let it rest for 5-10 minutes. The final temperature should be 135 degrees F.

Medium-rare: Cook the tenderloin to 140 degrees F, then remove from heat and let rest for 5-10 minutes. The final temperature should be 145 degrees F.

Medium: Cook the tenderloin to 155 degrees F, then remove from heat and let rest for 5-10 minutes. The final temperature should be 160 degrees F.

Medium well: Cook the tenderloin to 165 degrees F, then remove from heat and let rest for 5-10 minutes. The final temperature should be 170 degrees F.

Well: Do not cook beyond this temperature, or you risk overcooking and drying out the roast beef.