I had written a reply here previously, but when i pressed 'Post Reply' I suddenly got signed out and I lost it all.  Anyway, here's the basics of it....

That's Easy!  To complete the UEFI circle and take greater advantage of the system's hardware, faster speeds and responsiveness. In other words, you create a more efficient machine when you complete the UEFI environment.  However, it is advisable to build your own UEFI machine as the OEMs have too many restrictions, preload too much bloatware and make you jump through too many hoops to get a PC running to your liking and needs.  At least when you build your own you call the shots, decide which components to use and not use, which OS best suits your needs.

No, Doc, it is not!  Windows 8 is the POS [Powerful Operating System] UEFI is actually an escape from the restrictions of a Legacy BIOS. 

I am on my third UEFI motherboard now and I will honestly say that I've not had an issue I couldn't resolve in just a few minutes.  There were a couple of minor things, but those were due to user error while I was familiarising myself with the new UEFI environment.  Other than that, I've had trouble free use that has ultimately been a superior user experience to the Legacy builds I've done in the past.  Not only are the UEFI systems I've built faster and more responsive than the Legacy ones, they also seem more stable and reliable...no BSODs or system freezes to speak of.

Would i go back to a Legacy BIOS?  No! Not Willingly!  I do have a Legacy board here that I could possibly use in a pinch, but given I have 3 UEFI systems at my disposal, I do not see it'll become an issue any time soon

From what I read UEFI Partitions the hard drive with 4 partitions automatically in GPT mode and then installs windows.That means there is no MBR and you can't reparation and do a duel boot.The article also said you have to have a specially formatted DVD to boot up from CD drive. But didn't say how to make it. Might want to research that more,I didn't have time. It also said to boot from a thumb drive it has to formatted with fat32 to work.

Must have been that goofy...er UEFI bios....

I was able to dual boot finally.

I made the partition, using Windows built in disk management.

I went into BIOS, turned off UEFI and Secure Boot, enabled legacy options, set it to boot to the DVD drive.

Installed 7, then set BIOS back to defaults.

Voila!

Long way around the barn, but I got it done.

Well that's not my experience of things, not at all.  When I was ready to install Windows on my SSD there was only one partition.  From there, Win 8 created a "System Reserved" partition of 300mb, an EFI partition of 100mb, and the OS partition itself.

A UEFI system does not need a Master Boot Record like Legacy BIOSes, instead it records the installed HDDs in the GPT file.  However, this does not prevent dual booting should one wish to do so.  I also read that dual booting wasn't possible in a UEFI environment, so I [partially] tried to install Ubuntu on my UEFI based AMD FX 3850 rig, just to see if I could. I ran the installation disc and got to select the partition I wanted to use, and then I clicked install, which it began to do without hinderance.  I just didn't complete the installation because I didn't want to lose the rapid boot times I was achieving.

Also, I have a neighbour who dual boots Win 8 and Win XP Pro on his UEFI based machine, so it is possible. I just think there is way too much misinformation out there regarding UEFI and Windows 8, that people are possibly avoiding good and reliable systems on the basis of bullshit, for want of a better word/expression.  For example, I have performed reparations/recoveries in the UEFI environment without issue, either with Acronis True image or the native Windows recovery process, so that's not true.

What?  Really?  I don't know what that even means... or where the idea came from.  Unless they're talking really old hardware or some other issue from the Stone Age, that is totally rubbish.  I can boot from my Windows 8 disc, and I don't know that it is specially formatted.  I can boot from my Acronis recovery disc, and I didn't specially format that when I created it.  And for good measure, I'm going to try a Win 98 disc and an XP disc in my other UEFI machine.  Hang on!    Yup, just as I expected!  Both booted from disc.  So that's not true, either..

I dunno, I sometimes wonder if this misinformation is blatant bullshit, and if so, how do these 'media types' get away with it against some of the most powerful tech companies in the world.  Or alternatively, is it misguided opinion because the 'so-called' expert trusted to evaluate the tech had no clue what he/she was doing, therefore resulting in a completely unreliable review/assessment, whatever.  In either event, it makes me angry that the 'misinformation is allowed to remain out there to be embellished upon by another string of experts with an axe to grind.

I will admit that I was a bit hesitant at first, not knowing much about UEFI, but in having used it in 3 systems over the last 12 months, I will safely and categorically say that there is absolutely nothing wrong with it [until I have a reason to bitch about it].  Nah, seriously, it's damn good tech when used properly/as intended and isn't feched up by an OEM. with an agenda to drive.

Hehe, couldn't help myself, could I?  Had to wind up with a bit of a conspiracy theory, didn't I!  Maybe, cos I loves a good conspiracy theory, and it's way past my bedtime, it'll help me to sleep better.

EDIT!!!

Oi, what business have you, posting in between me and my intended quotee, and then go insult my goofy BOIS in the preocess?  You've been a naughty boy again, haven't you!  Now you're to big to go over my knee fer a good whooping with grandma's best teatowel, not to mention too far away, so as punishment I'm gonna give you negative karma until the cows come home.

BTW, I'm pleased to see that you got it sorted.    See, with a bit of determination and a few cuss words, anything's possible.

Well, I can say this much...this rig would not boot to a Easeus backup disc. It would not boot to a Windows 7 install disc, until I went into BIOS and disabled UEFI.

It would, however, boot to a system recovery disc that I made when I bought the PC.

When setting up 7 on this dual boot, naturally I started the setup from within 8, but on the first reboot during setup, the install errored because setup could not boot to the 7 install disk on reboot.

I had to again, disable UEFI boot options, and secure boot, in BIOS, finish the install, then reset BIOS back to defaults.

So, It does need to be a certain format to the disc in order to boot to it, without disabling UEFI in BIOS first.

Starkers, your setup may be different. I can only report what I know to be the case with my rig. It is an OEM, whereas yours you self built. OEMs are locked down, as we all know.

Even HP support told me it couldn't be done, only because they weren't gonna tell me to alter the BIOS.

Of course my setup is different!  Unlike those OEMs, mine was assembled with TLC and a kiss or two along the way.  I wanted it to know that I love it, and that after turning her on I would still respect her in the morning.  Now them OEM folk don't do that, no siree, and that's why their machines have inferiority complexes and never seem to work quite right.

I guess that's what I was trying to say, that I sidestepped a lot of issues the OEMS build into their systems by building my own.  The main thing is that you have overcome the obstacles they placed in your way to achieve what you wanted from the machine, and good onya.  Like I said before, anything's possible with a bit of determination and a lot of cuss words, hehe!

Lots and lots of cuss words. I even had to make up some new ones to hold back redundancy. 

HP Non Support brought a few new ones outta me!! 

I would have preferred to built one, but I had to buy this thing on credit, best I could do.

Gets me in the livingroom with the missus, we's trying to get closer in our old age.    

Glad you got it going. It was verry late and I was reading trying to get tired enough to fall asleep.The article said the guy had to take out his video card and hook up to vga to get his system to boot also. So when I get to build my new rig looks like I have to do lots of research before I decide what to install and how to install it.  As a side question. Can you install operating systems on separate drives and still get them both to boot? Everything I've read talks of duel boots on a partitioned drive.

Normally, yes. Dunno about this UEFI shit.

I sit corrected. Once I reenabled UEFI, the Windows 7 install won't load. If UEFI is left disabled in BIOS, Both OSes load. But for some reason, then, my touchscreen doesn't work with UEFI disabled.

On top of that, there doesn't seem to be drivers for 7 for this rig.

I hate wasting a 500 GB HDD on a single OS. 

Guess I'm single booting.....bummer.

Good. I've read Win 7 64 can be installed in UEFI mode also so by using 2 drives there should be a way to get it to work that way. More research. HP has a history of special drivers for their laptops and not being fast about updating them. I have one too.

http://technet.microsoft.com/en-us/library/hh290675(v=WS.10).aspx.     This is a article that tells how to make a CD to boot into UEFI and other topics. Hope it helps.

Being that this is an All In One PC, I don't have the ability to have a second drive. And lack of 7 drivers for this PC makes it a moot point.

Not a big fan of HP, but I can't see them providing support if what your doing would void the warranty 

Yes, enter the UEFI bios and pick the drive you want to boot and exit.......

Two words...

Aitch Pee....