Is there any difference between this RAM?

http://www.newegg.com/Product/Product.aspx?Item=N82E16820231135

Or

http://cgi.ebay.com/4GB-Alienware-AREA-51m-m15x-m17x-m9750-m5550-Memory-RAM_W0QQitemZ330318457677QQcmdZViewItemQQptZLH_DefaultDomain_0?hash=item4ce883ab4d&_trksid=p3286.c0.m14&_trkparms=65%3A12|66%3A2|39%3A1|72%3A1205|293%3A1|294%3A50

Its quite easy to install right? any differences?

i dont know exactly how easy it is to get to the ram on a laptop but you should just be able to stick the card right in and it will work

and also i would get two of these http://www.newegg.com/Product/Product.aspx?Item=N82E16820231131

but thats only 1GB so same as what i have nowxfactor19990

im sorry i was being stupid i would get this http://www.bestbuy.com/site/olspage.jsp?skuId=9360005&type=product&id=1218090910390 plus no shipping if you have a local bestbuy

how would i verify it accepts it? Im 99.9% sure it doesxfactor19990

do what i did just run a lot of programs that you know wouldnt work