I need cmpatible ram for my hp slimline 400pc 4010-314
currently has 4gb sky Hynix 2rx8 pc3 - 128000u - 11 - 12 - b1 hmt351u6efr8c - pb no aa 1415
Unless I am wrong, you should correct your question. I was unable to find any info on an HP 4010-314, but did find a 400-314. If you do indeed have a 400-314, the system will support a maximum of 16gb of PC3-12800 in a 2x8gb configuration. Best Buy, as well as many other stores, should carry or be able to order you this model of RAM. There are many very good brands such as Kingston, Corsair, Crucial, G.Skill, etc. A modest upgrade would be a 2x4gb kit, but for max performance you should go with a 2x8gb kit. If you go to the website of any of the manufacturers listed above, they each should have an easy to follow compatibility list where you pick your model and they give you their model/part numbers. Bestbuy.com does a terrible job with refining your search parameters, but you can search there with the model number you get from the manufacturer sites. Personally, I have used all of the above brands, and I have zero complaints (the last 2 systems I built I used G.Skill).
****Be sure you you buy the proper size modules, stay away from SODIMMs!!!****
****Apparently Best Buy does not carry PC3-12800 RAM, so you may have to look elsewhere (I was unable to find any on bestbuy.com that was actually sold by Best Buy)****