Abstract: An improved method for fabricating Chip-on-Board memory modules using partially-defective memory chips or a combination of partially-defective and flawless memory parts, comprises mounting unpackaged (or a combination of packaged and unpackaged) memory parts to a printed circuit board using one or more selectively settable materials, testing and patching the memory parts, and providing a protective cover after a suitable combination of memory parts and patches produces a fully-functional memory module. Also, a new set of printed circuit boards designed to allow fabrication of memory modules using single-bit patching, any-bit patching, and DDR technology with unpackaged memory parts. In a preferred embodiment, the method and printed circuit boards mentioned above are combined to produce a number of low-cost memory modules using modern, available partially-defective and flawless memory parts.