Greetings, i am a casual gamer who completed the first two games with pleasure. Perhaps i might not be a quite addict of these series but still finding the maturity of it so exciting.

However, i have never owned a serious gaming machine so far. Despite the fact not being a powerful notebook, the current rig ;

NOTEBOOK | < Msɪ ᴄx-61(ᴏNᴇ 445xᴛʀ) >

PʀᴏᴄᴇsSᴏʀ: Iɴᴛᴇʟ(R) CᴏRᴇ(TM)i5-3230M (2 PHʏsIᴄᴀʟ/4 VIʀᴛᴜᴀʟ Cᴏʀᴇs)
Gʀᴀᴘʜɪᴄs ᴄᴀʀᴅ: 2 ɢʙ NVIDIA GᴇFᴏʀᴄᴇ GT635M
SʏsTᴇM MᴇMᴏʀʏ : 8 ɢʙ DDʀ 3 (1600 Mʜz)

My settings ; Shown on the attached files ; Most settings on med, water quality and texture quality : high, grass related options are low , image res : 1280*768

runs the Witcher 2 : AotK as intended at nearly highest settings. On the other hand, i bought the third game in this June and haven't played it nonstop so far. Have recently returned and completed just the Devil by the Well quest.
The problem is when i make a record, the framerate displayed by the game is superbly low "even though the game
does not appear to be laggy, clunky or heavy".

i m aware the fact that my rig does not even meet the minimum system demands of the game. But, for instance DotA 2 at mostly loveliest graphics settings offers me 40-55 FPS, Mass Effect 3 at the highest offers constant 60 FPS whereas how much The Witcher 3 delivers? do not even ask me.

any ways to get decent FPS for such notebook at least 30 ?

No, not a chance, at least not consistently, and not on your settings. Even if you cranked everything down to 'Low', you'd still get areas of the game, and certain circumstances where your frame rate will drop. Forget the other games you mentioned, or any other game for that matter. The Witcher 3 is an incredibly demanding game, graphically, and your rig just doesn't cut it.