HP pavilion zv5476ea notebook. Took the more difficult choice and replaced the module under the key board! turned out to be easier than anticipated - 2 screws to remove the cover(the thin strip with the power button thru' it)which reveals 4 screws along the top edge of the keyboard,remove those and tilt the keyboard towards you to reveal the module. Open the latchs at each end of the module,it will pop up, pull it straight out, push the new module and press it down and the latchs will click over the ends of the module letting you know it is properly in place.Replace the keyboard and cover strip and the job's done. It took me about 10 minutes. Laptop booted up straight away(much much quicker than previously)and windows reqognized the module instantly.Will replace the other module(easy one under the cover on the underside - 1 screw) at a later date. Overall,easy and worthwhile upgrade.