Any 64-bit Ubuntu gurus? I need some help with a fresh install

[Freedom Kira]

So, I recently built myself a new server-like desktop computer. I installed 32-bit Ubuntu 11.04 and it seemed to work fine.

Then I remembered I actually bought 8GB of RAM, not 4GB, and therefore I would need a 64-bit OS. So I popped in the Ubuntu 11.04 x64 disc, and it was able to boot into the disc. Installed the OS, took the CD out, rebooted, and the system won't boot up. It hangs at a flashing underscore, akin to a command prompt.

I tried several things, including reinstalling Ubuntu x64 (well, the Ubuntu Desktop amd64 ISO) at least 5 times over, with or without installing updates while installing, to no avail. Any ideas?

Specs:
i5 2400
Gigabyte GA-Z68XP-UD3
8GB (2x4GB) G.Skill Ripjaws (PC3-10666, CL7)
Corsair Nova Series 2 CSSD-V60GB2 60GB SSD - boot
Hitachi Deskstar 0S03230 3TB 5400RPM SATA 6.0Gbps - 6 of these, for storage; haven't been initialized yet
Corsair TX650 V2 High Performance PSU
And some generic SATA DVD drive that I had lying around
*Note: I didn't buy everything from Newegg*

Tried using fdisk to set the boot flag, didn't work. Oddly enough, only one partition showed up, though.
Tried manually installing GRUB in a Live CD bootup, didn't work.
Live CD (actually I burned to DVD because they're cheaper) boots fine even when the installed OS doesn't.
Can't boot into Recovery Mode - can hold Shift for hours after booting with no reaction at all.

I'm about to download the 10.10 x64 ISO and install that instead, but I figure I'd at least ask here first. I wish I was more familiar with Ubuntu forums (or maybe I'm just a chicken who's too scared to post there).

[Lupin]

Then I remembered I actually bought 8GB of RAM, not 4GB, and therefore I would need a 64-bit OS.

A a 32-bit kernel with PAE allows addressing >4GB.

I tried several things, including reinstalling Ubuntu x64 (well, the Ubuntu Desktop amd64 ISO) at least 5 times over, with or without installing updates while installing, to no avail. Any ideas?

Did you check your media first before installing? Multiple reinstalls with the same borked media will yield the same results.

Try removing "quiet spash" from the kernel line when booting. This gives you the a list of what is being done while booting.

I haven't used ubuntu for years. I prefer working with RHEL/CentOS for servers and Fedora for desktops.

[rkruger]

Sounds like the bootloader was borked somehow when you installed the 64-bit version on top of the other one. Since it worked fine the first time.
I am not sure how much control you get over the bootloader part when installing Ubuntu? (I use Slackware myself), so there may be some automation in there that went wrong.

I would start from scratch by first deleting all partitions from the SSD disk using a live CD, this should hopefully make the install system "do the right thing".
To be safe, you should also disconnect the additional harddrives that you have while installing, as they may confuse the installation system. It may do something stupid like installing the bootloader on the MBR of one of those other disks.

[Freedom Kira]

A a 32-bit kernel with PAE allows addressing >4GB.

Interesting, I never knew about this. I guess using Windows most of the time will do that to you.

Did you check your media first before installing? Multiple reinstalls with the same borked media will yield the same results.

Try removing "quiet spash" from the kernel line when booting. This gives you the a list of what is being done while booting.

I haven't used ubuntu for years. I prefer working with RHEL/CentOS for servers and Fedora for desktops.

I'll try that after rkruger's suggestion below.

I've used Ubuntu at home for my NAS, Xfce and CentOS at school, and Kubuntu once or twice before. I'm just most familiar with Ubuntu, I guess.

Sounds like the bootloader was borked somehow when you installed the 64-bit version on top of the other one. Since it worked fine the first time.
I am not sure how much control you get over the bootloader part when installing Ubuntu? (I use Slackware myself), so there may be some automation in there that went wrong.

I would start from scratch by first deleting all partitions from the SSD disk using a live CD, this should hopefully make the install system "do the right thing".
To be safe, you should also disconnect the additional harddrives that you have while installing, as they may confuse the installation system. It may do something stupid like installing the bootloader on the MBR of one of those other disks.

Come to think of it, it had trouble installing the bootloader during my very first 32-bit install. I had reboot into the CD and "upgrade 11.04 to 11.04" and that fixed it. And I noticed that when I ran GParted, there was a notice by all the 3TB disks saying it couldn't find a partition table (something like that) except for sda (the SSD is sde).

I think I'll try clearing out the partition table on the 3TB disks and see if it starts up, and if it doesn't, clear the SSD and reinstall with no disks attached. I'll let you know what happens.

EDIT: Thanks, rkruger, I had to resort to installing with no disks attached to make it work. It might well have been installing the bootloader on sda for no reason.