The reason it looks so messy and crammed together is because there's no negative space. Every single part of the page is filled with something that it wants you to look at, so in the end your eyes don't know where to focus. Most websites have a primary focus in what their ultimate goal is for you to be on there.
If I'm a new customer; What's an "8 Pack", and why do I care? What is a "highlight" and why is it any different from a top seller?
Should these types of things be at the top distracting attention away from what your primary goal of the site is? I presume it's either to sell components or full systems.
The mega nav is a good addition, maybe not with the gradient on it, but the idea is good.
The 5 pods, is it necessary to say what each pod is twice, once at the top and once at the bottom? I'd remove the bottom text and black bar.
Is it necessary to have PC configuration right at the top, and then a couple of inches down to the left? Same with contact us where you have a contact us button directly above it.
People don't like being hit by ads as soon as they go onto a page, it's distracting, having a full width ad banner shouldn't be on the homepage, if you click sub components RAM, by all means show an ad for Ballistix, but not on the homepage.
Don't use as many dark greys and blacks it clutters the site too much.
There's so much that you could just remove which doesn't need to be there, to give the site more space, right now there's just too much.
I hope some of this feedback helps, but honestly it's a step backwards, negative space is your friend, and it does feel like this wasn't designed by a designer, but by someone higher up saying "I want this on here, and this, and this, and that" to which point there was no other option than to have a cluttered mess.