If you have your original system number, try hp's online tech support, which is usually free. I got online with a tech for almost 20 minutes recently to discuss ordering an hp backplate for a board I was trying to purchase. The tech was able to take me to the correct page for ordering the part with pricing, etc. I gave her top ratings when they emailed a questionaire about her service. She went out of her way to find an answer at no charge. I had another hp system, but was interested in a board sold at computer geeks. Even though I didn't purchase the board, I was pleased with hp's service.