The Intel I5-750 is a quad-core 64-bit processor operating at 2.66 GHz. The ASUS P7P55-M motherboard will support a maximum of 16 GB of system memory. Depending upon how much memory you have, you should be able to install most flavors of Ubuntu.
But you can also test it out for yourself before installing. Just download the ISO for any version and put it onto a USB flash drive. You can then boot from the flash drive and test out the version on your specific hardware.
The minimum system requirements for Ubuntu are:
- 64-bit dual-core 2 GHz processor
- 4 GiB RAM (system memory)
- ~25 GB of storage space on HDD/SSD
- VGA capable video resolution of 1024x768
- USB port for installer media
Other flavors of Ubuntu require fewer system resources. In particular, Lubuntu used to target low system resource machines. As of 18.04, they no longer specifically target "older machines". They will discontinue support of 32-bit processors after the 18.04 release. Many 10 year old machines, though, support 64-bit processing making Lubuntu a good choice for low resource computers.
Another option is Xubuntu. The minimum system requirements are:
- Intel or AMD 64-bit dual-core 1.5 Ghz processor
- 1 GiB RAM (system memory) not shared with video
- 2 GiB RAM (system memory) with integrated graphics
- ~20 GB of storage space on HDD/SSD
But Ubuntu will also run on the Raspberry-Pi and some other ARM processors.
The requirements for the Raspberry-Pi version are:
- a Raspberry Pi 4 for the desktop version
- a Raspberry Pi 2,3,4 for the server or core versions