A recent Google search for how to clear/reset/remove the BIOS password on a Dell Dimension L700CXE led only to misinformation. You can see discussions on forums where somebody asks the question and other people helpfully give the WRONG ANSWER. It is worse that just keeping quiet. I guess they feel like a guru for a minute, but of course when the guy who posted the question tries their advice, it won't work. Maybe if the "guru" posts his response in a sufficiently pompous tone, the guy who follows the advice will assume that HE did something wrong when it doesn't work.

Anyway, here is what worked for me. There is a jumper on the motherboard near the bottom (when the machine is in its normal position). The jumper is labeled J7A1 BIOS CONFIG. The normal operating position of that jumper is spanning the front two pins, as marked by the arrow on the motherboard. To reset the password, I unplugged the power, removed the BIOS battery, moved jumper J7A1 so that it spans the rear two pins. Then I booted the machine and entered the BIOS and was given the option to clear all passwords, which I accepted. Then I exited, powered down, put the jumper back to its regular position, replaced the BIOS battery, and booted the machine. It came up without asking for a BIOS password.