Does RAID or large capacity speed up data transfer rates?

tahoe5280

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If you get a normal HDD that is 40 gb---is it slower, faster or the same speed as using one that is 250gb (assuming the manufacturer and model are the same)? And is it faster to load programs if the disk is less full?

And I was under the impression that RAID 0 array is faster than a regular disk...is that correct?

My main use is for gaming, so my foremost concern is quick loading time---but a quick boot would be great too.
 

judey

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A smaller HDD won't be faster than a large one. In fact, I would think the opposite as these discs are the same physical size, so data on the larger drive will be packed in a smaller space, allowing less movement to access the same amount of data. But really, there's no difference.

Drive performance does slow down as the drive fills up as it begins to access data that is on the outside rings of the disc which requires more movement than the inside of the disc to access the same amount of data. But this effect is not detrimental, the real slow down would be the lack of space for windows virtual memory. As drives fill up, windows causes a lot of movement to find those fewer and fewer free spots on the discs to place virtual memory, so everything else in windows takes longer as a result.

RAID 0 (striping) is the fastest setup you can use. Basically two drives sharing the workload to provide maximum performance. read more about raid arrays here: http://en.wikipedia.org/wiki/Redundant_array_of_independent_disks

There are three HDD specifications that you should be checking to find the fastest drive for your money, RPMs, interface, and cache size.

RPMs is simply how many times the HDD can spin in a minute. Faster is better because it allows the HDD to access and send data faster. 5200 is outdated and slow. 7200 is the mainstream standard today and is decent. 10000 (WD Raptor) is the fastest available for a non SCSI, but much more expensive than 7200. SCSI can also go up to 15000, but again its expensive.

Interface is how the HDD connects to the motherboard. IDE(ATA or UDMA 66/100/133) is the slowest because it provides the least bandwidth. If you get an IDE drive, make sure it's the 133 version, you don't need to go any lower than that. SATA I (SATA 150, 1.5GB/s) or SATA II (SATA 3.0GB/s) are the mainstream interfaces today and provide significantly more bandwidth that the old IDE interface. SATA II provides double the bandwidth of SATA I. However, you really won't gain a performance boost between SATA I and SATA II because there isn't a HDD out there that can send enough data to use up 1.5GB/s.

For cache size, you want 8 or 16MB cache. Not much difference between the two in terms of performance.

I have two RAID 0 setups. One with two 36GB 10000 RPM SATA Raptors and one with two 160GB 7200 RPM IDE drives. The raptor setup is easily twice as fast as my IDE setup. I noticed those most easily in HL2 load times. While the load time on the raptors is annoying(i really hate loading screens), it's fairly short. On the IDEs, I could take a nice vacation to the Bahamas. Well, I haven't timed them, but like I said, the raptors are easily twice as fast and possibly three times as fast.
 

judey

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BTW...those raptors cost me over $200 for 72GB total a month ago. The 160GBs cost me about $120 for 320GB total a year ago. You gotta ask yourself if you wanna pay that much money for the performance increase.
 

Wapas

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The drive heads do not move more when accessing the outer parts of the drive, as the hdd rotation is constant, not like a cdrom. The velocity of the data passing is faster on the outer tracks. The disk spins at the same spindle speed, but the circle (2*pi*r) gives you the circumference or path lengh around that circle. So there is more data passing the heads at any given moment when the heads are on the outside. Now when your drive is fragmented and or full and the arm has to move from the inside to the outside alot to access a single file or group of files, it slows down the access times.
 

Madwand

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If you get a normal HDD that is 40 gb---is it slower, faster or the same speed as using one that is 250gb (assuming the manufacturer and model are the same)? And is it faster to load programs if the disk is less full?

Smaller drives in the same family (vendor, model and generation) are typically slower than larger drives. This is because larger drives will have more platters / surfaces (if not greater density as well), and require less track-to-track movement, and allow greater usage of outer cylinders.

Fuller drives are in theory on average slower than more empty drives because the chances for requiring longer seeks from one part of the drive to another is greater.

http://faq.storagereview.com/tiki-index.php?page=CapacityPerformance

http://faq.storagereview.com/