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I just got a new system and have been trying to get it set up w/ Win7 & Kubuntu dual-boot, but I've got a major problem. The BIOS of my motherboard (an Asus Crosshair 990FX) is strictly UEFI -- there is no legacy support mode available. I've been reading up on how to get Kubuntu installed in UEFI mode but no matter what I try I cannot seem to even boot into my install CD/USB key properly.

I can get as far as the selection screen ("Try Kubuntu", "Install Kubuntu"...) but this screen starts off not appearing correctly. If I try moving the cursor around it sometimes seems to correct itself and show me my choices. But once I select "Try Kubuntu" it starts loading, the screen goes black and then proceeds to flicker -- about once every 5-10 seconds or so. This continues indefinitely.

I've tried this with both Kubuntu & Ubuntu installation media, even the AMD64+Mac Ubuntu variety that is supposed to be a lot more flexible w.r.t. UEFI. The only hint I've had that the system might have booted correctly is a little drum sound that plays when booting from the Ubuntu install disk. Well, that and the fact that when I hit my system's power button it seems to shut down correctly, even ejecting the CD at the end.

This might be a video driver issue; my system has two nVidia 550's, one of which is attached to my primary monitor. (The secondary isn't hooked up yet.) I'll keep looking over similar questions but any advice would be greatly appreciated.

UPDATE: I've tried booting into my 12.04 install CD twice now, each time using two different options supplied by my BIOS. One seemed to offer the ability to boot into my CD under UEFI mode -- this didn't even produce the initial boot menu. The other method offers the ability to boot into my CD NOT under UEFI mode. This DOES produce the boot menu, but after this point it seems I still cannot get to a proper video mode to see what's going on.

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I do not thing that it is an UEFI issue, otherwise you would not be even able to start booting from your CD, not to mention getting to "Try Kubuntu" screen. I bet it is a video driver issue. – January Sep 28 '12 at 10:28
Agreed. I'll see if anyone else has had video card issues while booting. – Beatbug Sep 28 '12 at 10:50
Could it work by connecting the monitor via HDMI only, as this connects directly to the onboard graphics card? – user93925 Oct 3 '12 at 12:35

Just an update: I was able to get video by supplying "noacpi" and a VGA mode; one of the numerous Ubuntu articles about UEFI was helpful here, though the specific paragraph about trying out various parameters seems to have been edited out.

My Origin system appears to use different verbiage to indicate whether to boot from USB using legacy or UEFI; in my case "legacy" was indicated by "PMAP".

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The drum sound you mention indicates that Ubuntu successfully booted; that's the standard login sound. This means that your problem is definitely one with the video support.

The solution might be hardware-specific or it might be more generic, such as adding the nomodeset kernel parameter to the boot loader options. (I don't recall precisely how to do this with the Ubuntu install CD, though; maybe somebody else can post that information, or you could try Googling it.)

Another option is to try another distribution; sometimes one runs into video problems and another doesn't.

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