csabee:
I have a 1.8 SPI TFT also from ebay, but my problem is that I have a 16pin pcb.
This is exactly the one I have. You can use the wiring table above.
The mega requires slightly different wiring, because the hardware SPI is on different pins. Just read the comments in the adafruit example sketch, it is explained there.
Can you test the example sketch? Do you experience the same issue than me?