Dropclock is actually considered as a compatible type of Microsoft Windows screen saver. It's most-commonly found in Dropclock 1.02 developed bytha. It uses the very popular SCR file format and is therefore considered to be a Win32 EXE file. The reason why many people consider it a compatible screen saver is because it can be easily removed by any Windows system, even after uninstalling the program.
To conclude, dropclock is a very easy and efficient program to use as a power Windows optimizer. However, its main flaw lies on the fact that it just duplicates your current desktop wallpaper and gives it a white background. Although it may seem like a very minor problem, this can cause serious problems when trying to make your computer faster. You should try to remove the duplicate background or move it to a clean area of your hard drive to get best results.