lag with TightVNC

I have set up my PocketCloud client with TightVNC on my Kindle Fire but it lags to much. When I try to close a window it just shows a shadow. I have a very fast WiFi connection but it just lags to the point of unusable use. Is there a better client for PocketCloud compatibility? I'm running Windows 7 Home Premium 64 Bit on Intel processor. Thc.