Since you cannot replace the driver, you must change your workflow. Here is how to make the GMA 3150 feel "better" without hacking drivers.
Because the GMA 3150 lacks hardware decoding, your 1.5GHz Atom must decode video via CPU. The "better driver" doesn't exist for this; only better software. intel atom n550 graphics driver better
Many users mistakenly attempt to install the "GMA 3600" or "GMA 3650" drivers (designed for the Atom N2600/N2800 "Cedar Trail"). Since you cannot replace the driver, you must
If you want “better graphics performance” → switch to Linux (antiX / Puppy).
If you must keep Windows 7 → use the Intel 15.12.75.4.64.2230 driver, not newer, not generic. If you want “better graphics performance” → switch
Do you want a step-by-step Linux install guide for that Atom N550 netbook?