creating posts in forums

I need to create posts in high PR forums that are related to maintaining and repairing PCs. It is actually creating backlinks to my site by placing a signature to every post. Every post must not look like spam and be approved. All posts must be different from each other and written on different subjects regarding PCs, LCD displays and LCD TVs. All posts MUST be original and not copied from other forums and posts! It is better you have a technical knowledge and know what you are writing about. In the beginning i need to create about 100 posts - 10-20 posts per week. Thank you