If your computer is still not turning on, you will need to clean the memory sockets, video card slot, and CPU socket, as it may be a bad contact between these components and their sockets. You will need to buy isopropyl alcohol, a pencil eraser, and a tooth brush, all available at any supermarket. (Ideally you should buy an anti-static brush, but a cheap toothbrush will do the trick.)

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Figure 4: Material needed to fix bad contacts

Remove the CPU (you will need to remove the CPU cooler first, of course), the memory, and the video card from the motherboard.

You will clean the edge contacts from the video card and the memory module with an eraser as if you were “erasing” them, as shown in Figures 5 and 7. Do this far away from the computer, and do not touch the edge contacts (a.k.a. “golden fingers”) after cleaning them. You should clean the edge contacts available on both sides of the memory module and video card. After rubbing the eraser, clean the edge contacts with the toothbrush wet in isopropyl alcohol.

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Figure 5: Clean the memory module edge contacts with an eraser

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Figure 6: Then clean them with a toothbrush wet in isopropyl alcohol

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Figure 7: Clean the video card edge contacts with an eraser

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Figure 8: Then clean them with a toothbrush wet in isopropyl alcohol