If you have waited for an hour, the the system may be trying to load a driver for some device and is having problems. It may also be looking for something on the network and can't find that. If this were happening, you might try going into the Bios and disabling whatever you could which may include Bluetooth and Wi-Fi. If you have external devices, including an SD card installed, remove them. Basically, make you system as simple as possible.
Starting from a powered down condition or a restart will have different results, so make sure and try both. Try going through the Bios setup page first.
I suppose it might also be helpful to know if you had performed any changes to your system, such as software or new device.
Have you seen any notifications about updates being performed?
And don't wait for the logo to appear, in some situations, that is too late.