kochiB :
thanks for ur inputs but guys , its not a desktop . am looking for a notebook , who would buy a branded one if it were a desktop ...
dell 15 and 15R are notebook series
Well im not sure why they thought Desktop when the cpu with "m" at the end of it meant mobile.
http://ark.intel.com/Product.aspx?id=47663
Anyways, for your questions,
o1die statement about the ram speed is still valid. There little noticeable difference between the 2.
the doubt comes from the place that i am confused which one to chose between the dell inspiron 15 and 15R series .
Can you lead me to this Inspiron 15r laptop? I found the inspiron 15 although I cant seem to find the 15r on dell website.
http://www.dell.com/us/en/home/notebooks/inspiron-1564/pd.aspx?refid=inspiron-1564&s=dhs&cs=19&~oid=us~en~29~laptop-inspiron-15_new_cto_3~~
also is it possible to replace the graphics card they are offering as per the website with a card of my choice , i mean does dell allow that ??
Well what are you meaning by this, Can you replace the graphic card down the road or choosing a gpu for a laptop before buying?
If it's the choosing gpus before buying, Well on some models of laptops they can, some others not, although if you do have an option of graphics cards, you normally limited by 3 choices and sometimes less.
In your case, You have 2 choices with the Inspiron 15.
For grapics, you can stick with the default ATI HD Mobile 4300 or for $270 more can get an Ati HD Mobile 5450 (that $270 also includes a faster core i5 520M but a smaller 320GB HD than the normall 500GB)
http://www.dell.com/content/topics/topic.aspx/global/products/ltd/en/us/dhs/inspiron_15_dndov31?c=us&cs=19&l=en&s=dhs
....
If you were meaning swaping card down the road, Well i dont think dell likes/supports that. There more of the fan of if you want to upgrade, you need to buy a whole new system than upgrading parts.
Although the question i should of ask at the beginning of this comment, What will you be using this laptop for and whats your budget?
If you tell us though 2 things we might be able to find you a better laptop for a better price than what your looking into currently.
Hope the info so far helped.