Replacing my motherboard - expertise required?

Hi all,

My PC has been out of commission for a few months due to moving house and I've recently plugged it all back in to begin using it. However, I've noticed that my PC won't utilise the full 8Gb of RAM currently installed, although it does recognise it. Now, I've gone down the diagnostics route (Yes, I'm on Win7 64Bit, have reseated all DIMMs including one at a time, ensured BIOS settings are correct, even put in a blank hard drive with a new image on it, just in case). The end result I've found, is that two of the DIMM slots on my motherboard (ASUS® M5A99X EVO) appear to be faulty, these two slots make up one half of each pair. So no matter what I do, my PC never runs on more than 3.95Gb of RAM.

Now, to the thread title at hand. It's become clear that to fix the issue and allow for future upgrades, my motherboard will need to be replaced. I've swapped out all of the internal parts in multiple PCs in the past, but I have never replaced or removed the motherboard and CPU. So my question really is, how easy is it to replace the motherboard? Will I need to remove and reapply thermal paste? Are there any specialist tools I require?
If need be, I might try to request PCS replace it, but not sure that's something they'll do when I ordered the PC back in early 2012.

Thanks in advance for any response.

The motherboard is the most difficult component to replace in the PC - if you're wanting to do it yourself it certainly can be done and isn't that bad if done methodically. It will involve removing pretty much every other component out of your case (maybe except for the PSU, although I'd probably consider removing all of the wires and starting from scratch if it was me).

You will need to remove your CPU cooler and potentially might even need a new CPU assuming the motherboard you're getting is new (might not be the same socket as your old one) which means that you'll need thermal paste etc. to re-attach the cooler.