Remove the cpu or memory; either one will tell you if your board has enough speed to justify the cost. Many memory sticks have the id label intact; pc133 is old sdram, and motherboards are harder to find; pc2100-pc3200 has enough speed to warrant further investigation; and ddr2 is labeled at 3200-8500. For the cpu, any upright cpus such as the Intel p3 450 up to the original athlons that sit in a slot looking like a large memory stick with a cover aren't worth salvaging; they use pc133 sdram. All newer cpus will sit flat and have a square shape. And newer power supplies will have at least 220 watts; Anything less I would toss out. The faster p3's will also be square shaped and use sdram; their value is for internet use only.