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This is really a question about whether or not it is absolutely necessary for me to upgrade my Fedora.

I just upgraded my computer with a couple more sticks of RAM and have it up to 8G now. I duel boot so I know that Vista (64bit) recognizes my 8G, and Memtest86+ recognizes my 8G, but for some reason Fedora 9 (64bit) says it has 3.1 G RAM. Is this a problem with Fedora 9 (64bit) or is it some configuration thing I've missed?

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Since Fedora 9 is no longer supported, I'd strongly suggest that you update regardless. See – developmentalinsanity Feb 1 '10 at 13:49
I know I should, but i want to know if I need to in order to get all my RAM. – Robbie Feb 1 '10 at 14:25
up vote 1 down vote accepted

Just re-download a kernel and re-compile it, including 64GB RAM support. Your kernel is just not supporting more than 4 GIGs right now.

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Is there something special I need to do in order to include 64GB RAM support, or is that just dependent on the kernel that I download? Should I get the latest kernel (, the kernel that I am running (, or the latest sub version of the kernel that I'm running ( I don't want to break my existing install. – Robbie Feb 1 '10 at 17:04
All kernels have the option available. It's a matter of selecting it. Sadly, I have never compiled my own kernel in Fedora and do not know what specific steps you need to take in order to not break any automation - but on that level, Google can help! If you're lucky, you may already have the source for the kernel available - for me, with Gentoo, they are under /usr/src but I am not sure where they are for Fedora. You may be able to get them from yum. If you compile a kernel that doesn't work -- just boot from the old kernel! – Trevoke Feb 1 '10 at 17:17
Thanks, I'll give it a shot and give you a check if all goes well. – Robbie Feb 1 '10 at 17:19
I couldn't find the option for 64GB support in gconfig with the 2.6.27 linux kernel. I'm going to try again tonight, though I couldn't really find any good sources of information about that particular config flag. – Robbie Feb 2 '10 at 14:37
Here, take a look at this article. I hope it helps: At the worst, you may need to patch the kernel (easier than it sounds) or download a pre-patched / custom kernel (safer than it sounds). – Trevoke Feb 2 '10 at 18:33

You can also install a 32 bit Linux, and install the bigmem kernel. Then supports 64 GB ram on a 32 bit system (if CPU >= Pentium 4)

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