having 8 GB of RAM but only 320 GB of 7200rpm hard drive?

Is this feasible? Will any bottle necking occur at all?

 

HDD will always be a bottleneck at all times it's being used.

 

You will be fine. The only issue is if you need more harddrive space for storage.

 

I assumed that the only downside to having low HDD space is slower app launch speeds, slower boot speed and less space. I don't think it affects "speed".

 

Available space doesn't directly affect boot or launch speed. If that drive if a Scorpio Black, it's one of the fastest mechanical drives you can buy.

 

Actually, at the same RPM the smaller the drive the faster the load time because the shorter the search distance.

 

completely untrue. The larger the drive, the higher density the data, the shorter the search distance (assuming drive is not fragmented)

 

You transfer rate is always dependent on the platter size (physically) as well as rotation speed... That's why a 3.5" will always transfer faster than a 2.5" at the same speed. However, what I said earlier is not quite valid. Notebook drives actually vary between 1 and 2 platter designs.

I was figuring that as all 1 platter designs, the smaller drives are probably using the same platters, just artificially limited to not use internal tracks. (Search distance thus is limited). Most companies produce a limited set of platters, so its not like the distance between tracks is different between a 250gb and a 500gb drive most of the time. Usually the 500gb just gets the inner 2/3 of its radius shut off and you have the 250gb drive.

In the situation I stated above, provided your drive is the same % full, search distance is shorter on the 250gb. However performance should be virtually identical up to the point where the 250gb fills.

This is predicated that we are on 1 platter designs (which I found out isn't necessarily true), and that the drives you are comparing are using the same platters. (Which was an assumption I shouldn't have made).

That said, data density doesn't help you at all. Performance comes from not using the internal tracks on the drive where rotation speed is much slower, and usually smaller drives are actually limited larger drives so their performance at the same % capacity will be better, but should be the same as the larger drive (properly defragged) up until their limit in size.

 

Now that you have clarified your assumptions - I agree