If the PC does not start after the BIOS splash screen, it may because your hard drive has no data, or is disconnected or faulty. Unfortunately you have not provided very much information about the nature of the problem. Since you say you see a splash screen, it`s safe to say your components themselves are in good working order, which leaves the computer with the possible problems i listed above. As for your DVD writer, I`m not surprised it works, I don`t see why it wouldn`t. You may not be able to access the drive because it is not set to boot before the hard drive in the BIOS boot order. If you can give us some more information, perhaps we could help you some more.