http://www.newegg.com
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If you want to buy a million DVD burners or hard drives, I’m sure any name brand manufacturer would make a deal with you. For us common buyers, search the internet for best deals. Try pricewatch.com or eBay to find deals or cheap parts. Look at local computer ads for rebate deals, sales and special promotions.
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There are literally hundreds of web sites with low-cost computer components.

By far, my favorite is: Newegg: http://www.newegg.com/
Their site is by far the easiest to work with with very powerful search tools. It’s incredibly easy to drill down into a category then pop back up or search for a part with a half dozen parameters using their Power Search. Newegg’s prices are always low, if not the lowest. You can set up wish lists to save carts, share the wish lists for comments, etc. Almost all components will have a set of user reviews often numbering in the hundreds or thousands.Reasonable-cost 3-day shipping (which often only takes two days for me). Just a great place to shop. I’ve been buying stuff there since 2001.

Others in order:

MWave: http://www.mwave.com/mwave/index.asp Not as easy to navigate as Newegg and generally has nearly the same prices – occasionally lower. I sometimes use MWave when Newegg is out of stock on an item. MWave often has some good deals on barebones systems and CPU/motherboard combos with and without memory included.

TigerDirect: http://www.tigerdirect.com/ Another site that’s occasionally cheaper than Newegg, but usually not. They sometimes have things others do not. They often have really good sales. They also have some very good barebones specials. Their navigation used to be horrid, but seems to be getting better. I used to only be able to find something if I knew the exact name/model number. The site in general just seems to be improving.

NCIX US: http://www.ncixus.com/ NCIX, as near as I can tell, was the "Newegg" of Canada. Now that Newegg Canada (Newegg.ca) is up and running, I guess NCIX felt like they should reciprocate and open a site in the US. Their prices are generally slightly to considerably higher than Newegg, but they have some really good weekly specials.

Cooler Guys: http://www.coolerguys.com/ Not a place you can get all components, but they have lots and lots of cables and cooling solutions. I look here for fans, passive, water cooling, case mods like lighting and window kits. I get a lot of my cooling stuff here because they are often cheaper than Newegg when shipping is added. Newegg charges as much to ship a fan or cable as the fan or cable costs. I think this site and http://www.pctoys.com/ are the same site. My only complaint about PCToys is they are in Washington state and I’m on the east cost. Shipping takes 5-6 days.

Silicon Valley Compucycle: http://www.svc.com/ Another place to go for fans, cooling, lighting kits, etc. If you are interested in building a quiet PC with passive cooling, case sound insulation, anti-vibration hard drive mounts and the like, this site has that. That’s how I discovered them.

A site that sells nothing, but that you really must get acquainted with is Reseller Ratings: http://www.resellerratings.com/ Type in the name of a site you are thinking of doing business with and see what others thought about them. The reviews are independently written by actual buyers (although there has been some claims of fraud to have good reviews posted by fake reviewers, reviewers get a coupon or gift for a good review, etc.). This is definitely a place to check before submitting an order with someplace you haven’t done business with.
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