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I was reviewing my settings in BIOS and UEFI was disabled. I wanted to check what UEFI was so I googled it. I found out its like an upgrade to BIOS and improved boot speed. Currently I'm dual booting Ubuntu 12.04(32 bit) and Windows 7(64 bit). I'm currently confused as to how to make the switch since I don't want to make my System unbootable. How do I make the switch from BIOS to UEFI.

System Chipset : Intel HM55 Processor : Intel Pentium P6100 2 GHz

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If you're prepared to wipe everything and start fresh it's not so bad. I recommend:

  1. Clear the partition table (dd if=/dev/zero of=/dev/sda bs=512 count=1).
  2. Partition with GParted, parted, or gdisk. Be sure to create an ESP with a FAT32 filesystem. Make it 200-500 MiB in size.
  3. Install both OSes. Order is less important than on BIOS systems, but back up the ESP after the first install. Pre-12.04 versions of Ubuntu would wipe the ESP, and hence the Windows boot loader, when installing. That was supposedly fixed in 12.04, but I ran into it on my latest installation, so I don't think it's been completely fixed.

I wouldn't worry about the 2GB RAM, but it depends on how much stuff you run, really. Benefits will be minor -- mainly a possibility for an improved boot time and, once you learn it, easier boot manager maintenance. There'll be a learning curve, though. Check my Web page on EFI boot loaders for information on what's available and how they work.

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That cleared a lot of my doubts. But the thing is I have to Enable UEFI and then launch the Shell file. I'm currently confused as to how that'd work. As in once I launch the shell file what happens next? I have no clue whatsoever. If you could clear that part of my doubt it would be great. – Schweinsteiger Aug 15 '12 at 19:26

It'll be a lot of work.

In Linux, it could be done by carving out an EFI System Partition (ESP) on the disk, installing any of several EFI boot loaders on that partition, and reconfiguring the firmware to boot in EFI mode. For some firmware, you might need to convert from MBR to GPT and/or remove all traces of a BIOS boot loader, but some firmware implementations don't require this.

It gets harder in Windows, since Windows requires jumping through additional hoops to switch from BIOS-mode to EFI-mode booting. Some of those might be required by your firmware even when booting Linux, though, like the MBR-to-GPT conversion.

In sum, unless you're re-installing everything, this will involve a lot of work on a dual-boot system, with very little practical benefit. You'll also be risking total loss of all the data on your hard disk. Thus, I can't really advise this except as a learning exercise, and then only if your data aren't important.

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I have all the data I need in an external Hard Disk. I actually dont mind doing a full Wipe of the hard disk. I have seen Videos where people just switched from BIOS to UEFI and Installed windows. The windows 7 installer itself did all the required partitioning. What if I install Windows 7 like that and then Install Ubuntu. Would I still have to all the work that you mentioned. And Finally, Is it really worth doing all this? Since Only 64 Bit OS's support UEFI and I have only 2GB DDR3 RAM and I have heard anything less that 4 GB is practically useless. – Schweinsteiger Aug 15 '12 at 10:28

Apart from having no benefit there is also the risk of updating the UEFI (formerly known as BIOS update) and losing all boot information data for the EFI boot loaders. It's not difficult to enter them again via EFI shell, but it's something that should not happen (never happened with BIOS/legacy boot) and leaves your system in an unbootable state.

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