what does 3 beeps mean?

I was working on my early 2011 Macbook Pro running Snow leapord last friday when the screen froze and 3 beeps eminated from the machine.

i did a hard shut down, restarted, ran Disk Utility which told me my Hard drive was corrupted.

ReBooted from my installation CD, repaired disk, all well and good.

I ran a Hardware test which told me all hardware was working.

So, today same thing happened. Verfied disk which told me HD was corrupted again and needed repairing. Reran through above steps to fix all well and good.

Except immediatly beeping started again. This time Disk utility told me HD was fine tho.

Ive booked an app at a Genuis Bar tomorrow but going through the archives here i see a 3 beeping scenquence is associated with a RAM issue.

Now this is interesting as 3 months ago i did update my 4gb RAM that came installed to 8GB Crucial sticks. The RAM was installed properly and havent had a problem since. This was 3 months ago

So i checked my system, Both my RAM sticks (4gb each) are recognises and system says they are working. They are by Crucial and the correct for my notebook model and type- have been working absolutley fine since install.

Can i still take it this is a RAM problem? Im assuming this problem is not fixed.

IS the fact i have had 2 reports of corrupted HD from Disk Utilty within days of eachother as relevant ?

Surely my HD shouldnt corrupt again within days of being repaired and as it has, is there anything i can put this down to or totally unrelated to the 3 beeping? Bit coincidental though if not?

Unfortunatlely, i dont have the original RAM sticks anymore to replace and test with.

Any help, oh mac boffins for a lady in distress? 😉