Define "reliable." The centrino works just fine, but I find the definition of what you are asking to determine how to reply to that.
Given it's a laptop, you will find that the battery will likely need replacing just about 18 months out. As such, this could in itself be considered an unreliable battery. But this is the state of the art for the price we are paying for these units.
Also, since it's not a ruggedized laptop, it doesn't survive a fall from the desktop to the tiled floor. This could be a reliability issue.
And then we have that pesky OS issue. Just leaving the preview enabled in Outlook Express can cause the machine to become infested with any number of parasites. That's 3 counts against "reliable" but all but that rugged (and more expensive) laptops have these issues.
Tell a bit more...
As to Centrino or P4, all the dirty details are at www.intel.com in the developer links. But I suspect your questions are not about the details but something else. Spell out one question at least here.
As to shared video memory. It's a cost cutting move that results in usable laptops at lower costs, but never delude anyone to think it will play games like a real video card.
I am not sure if anyone can help, but I have a few questions about a dell inspirion 300m notebook I want to purchase. The first question I have is concerning the processor. The specs list it as a intel pentium m processor and I'm not sure how this differs from a intel pentium 4. Second, the standard memory is 256mb shared memory. I've been looking through various sources and I can't determine whether shared memory is better or worse than notebooks which don't use this. Finally, I have not checked but I was wondering how reliable intel centrino technology is. If anyone has the time and doesn't mind answering it would be appreciated.