5400 vs 7200 rpm on a Z

OK guys..Whats the word on this one...Sure its faster but will 7200rpm cut battery life? Opinions??

 

Not by much, and in most cases there will be no loss of battery life.

The 3 favorites around here are the WD Black, Seagate 7200.3 and the Hitachi 7K320.

 

Is VAIO Z HDD Interface SATA or SATA2? Can I use any SATA2 HDD or I need the one with definite SATA support?

 

Is it REALLY faster? Sure it spins faster but that does not automatically mean it will have better performance. The real numbers you want to look at are transfer rate and latency.

To be more specific, a higher density 5400 drive may have better transfer times than a lower density 7200 one. If the two drives are the same size (density) then of course, the 7200 one will win out.

Gary

 

Scorpio Blue = 5400rpm
Scorpio Black = 7200rpm
http://www.laptopmag.com/advice/expert/are-ssds-worth-the-money.aspx?page=5

 

Anyone know which brand 320 7200rpm drive the Z ships with?

 

Even with much higher density on a 5400 rpm drive, it will almost always have worse access times.
The average time to get to any data point after the head has moved into place is half a revolution, and with 7200 rpm, each half-revolution takes ~4.1 ms, while for a 5400 rpm drive, each half-revolution takes ~5.6 ms.

(There are tricks to reduce this, like NCQ (native command queuing), where multiple queued up requests are done in the order that has the least amount of overhead, and not in the order they were received.)

Lightning fast access times is why SSD drives win even when their transfer speed is slower. Unless you do large file sequential access, go for faster access times over faster transfer rates.

 

When a hard-drive spins up (which uses power), it also remains spinning until a few minutes after it becomes idle (selectable in system > power options).

So if you have a 7200 RPM drive spinning up to load/save a single file every now and then, the drive will continue spinning at full revs for 3 minutes or similar each time afterwards, and thus it's gonna soak up more battery juice than a 5400 RPM would for the same duration as the 5400 uses fewer revs.

A 5400RPM SATA2 hard-drive should already be pretty fast, and will give you an additional 30mins of battery life over 7200RPM depending on how you use it. Heat is a killer for hard-drives, and on particularly hot days the temperatures of a 7200RPM drive running continually could stand to rocket. The heat from a 5400RPM drive would be less so.

There's pros and cons for both 5400 and 7200 revs. Depends on what you are intending to do with the laptop. Desktop performance with a compromise on battery life: 7200RPM. Mobility: 5400RPM.

 

No question that the access time is slower. But the transfer rate can more than make up for it, in certain cases. Note that the operative word there is CAN. But the entire point of my comments were that RPM is NOT the figure you should ever concern yourself with when comparing drives. Access time (latency) and transfer rate are ALL that matter. RPM being touted as the deciding factor is marketing propaganda. It's all about the throughput.

RPM, access time and transfer rate each by themselves cannot measure throughput. You need the sort of real world tests like HD Tune to see those winning number that SSD drive exhibit. Looking at the raw stats for access time and transfer rate won't give the average Joe any real insight. For same sized/geometry drives, RPM can be pretty much used as a banchmark for faster versus slower. But the moment the sizes, head count etc change all bets are off and real TESTS are needed.

Gary

 

Hitachi TravelStar HDD.

 

Bzzt, wrong. You just flunked Newton's 1st law. Inertia is what keeps the plate spinning, not the motor. Once it's spun up, the only force needed to keep it spinning is enough force to overcome friction, and the friction is not measurably higher for a 7200 rpm drive than a 5400 rpm drive.

What takes more power is to spin up the 7200 rpm drive to full speed in the first place. But to keep them spinning, no.

You may be too young to remember record players, but some of the best ones were driven by a deliberately underdimensioned motor using a rubber band. To get the platter up to speed, you had to manually rotate it, after which the rubber band took over the very light task of just keeping it spinning. And the motor worked just as hard for 33 rpm records as for 45 rpm records, or 78 rpm shellacs for that matter -- you switched gears by moving the rubber band to a different sized capstan.

 

7200.4 Seagates new 250gb / per platter is on par with desktop hard drives. I have always upgraded drives and have owned Hitachi 60gb, 200gb, and Seagates 320gb. The 500gb 7200.4 blows everything I had previously away. The improvement is very noticeable.