For me easy;
1) The Dell Inspiron 15R i5 Notebook PC comes with an Intel i5 processor, model 2410M (2.3GigaHertz frequency rate),
It uses DDR3 at 1066MHz, (Why would you?), or DDR3 at 1333MHz, and up to 8GB's of it.http://en.wikipedia.org/wiki/List_of_Intel_Core_i5_microprocessors#.22Sandy_Bridge.22_.2832_nm.29_3
It has Intel HD Graphics 3000 graphics built-in. (It's in the Intel Core i5 processor. It is Integrated Graphics)
2) The Toshiba Satellite L755-S5173 Notebook PC, comes with an Intel Core i5 also.
Model 2450M Intel Core i5 processor;http://en.wikipedia.org/wiki/List_of_Intel_Core_i5_microprocessors#.22Sandy_Bridge.22_.2832_nm.29_3
It comes with an Nvidia GeForce GT525M graphics chipset.http://en.wikipedia.org/wiki/Comparison_of_Nvidia_graphics_processing_units#GeForce_500M_.285xxM.29_series
A LOT better than the Intel HD Graphics 3000 GPU (Graphics Processing Unit), above.
From what I can see it is a graphics chipset soldered to the motherboard,http://www.irisvista.com/tech/laptops/Toshiba-Satellite-L755-L755D-L750-L750D/dismantle-laptop-3.htm
Click on the photo in Step 27. Bottom view of motherboard.
Look at the black Fan Assembly, and the copper curved Cooling Tube.
Go over to the far left of the Cooling Tube, to the rectangular silvery shape. Has 4 black screws in it. (This metal plate sits on top of the Processor)
In-between this rectangular metal plate, and the bottom of the motherboard, is the Nvidia graphics chipset.
Square dark green shape (Circuit board), with a smaller dark square shape in it. (GPU)
Means it isn't a graphics adapter card, and therefore not upgradeable.
Uses DDR3 Sdram (SO-DIMM) 1333MHz ram memory, and up to 8GB.
3) Lenovo G470 Notebook PC has an Intel Core i5, Model 2450M also.
UP to 8GB's of DDR3 Sdram (SO-DIMM) ram memory, at 1333Megahertz, too.
Intel HD Graphics 3000 is used also. (Integrated Graphics)
The Toshiba Satellite L755-S5173.
One of the things you ALWAYS look at for a laptop, because 95 percent of the time you cannot upgrade it.
(A LOT of laptop manufacturers state - Graphics Card, when the truth is it is not a replaceable graphics adapter card, as used in a desktop computer )
This means you are stuck with the graphics of the laptop, until you obtain a better one.