A hard disk drive (or HDD) is a non-volatile, random access device for storing digital data.

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891
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What are the Windows A: and B: drives used for?

In Windows you have a C-drive. Everything labeled beyond that is with the following letter. So your second drive is D, your DVD is E and if you put in a USB stick it becomes F and the following ...
237
votes
10answers
23k views

Why is Google so much faster than a hard-drive search?

When I search a file on my HD in Windows 7 or Windows XP it takes some minutes to finish the process. If I fill in a search term in Google, the answer is on my screen in milliseconds How is it ...
200
votes
10answers
57k views

Is there still a reason to choose a 10,000 RPM hard drive over an SSD?

For anyone who's serious about storage performance, SSDs are always the fastest solution. However, WD still makes their 10,000 RPM VelociRaptor hard drives, and a few enthusiasts even use enterprise-...
189
votes
4answers
13k views

What is the purpose of the holes marked “Do Not Cover” on hard drives?

On many hard drives, there's a text warning to "not cover this hole", sometimes adding that doing so will void the warranty. What is the purpose of this hole and why would covering it cause damage or ...
143
votes
18answers
312k views

What utility can move my Windows boot partition over to another hard drive? [closed]

Can anyone recommend a cheap/free utility that can do this without very much effort? My preference is that it would be really easy. Boot into Windows Pick drive to move Pick target drive It copies ...
107
votes
4answers
10k views

Why do damaged hard drives freeze the entire system?

Why does a hard drive which is known to have bad blocks (verified in HDTune and HDDScan), freezes down my entire system? It is not the OS drive; it is attached to another SATA port, and I'm trying to ...
86
votes
9answers
30k views

How can I wipe a broken hard disk drive before sending it back to the manufacturer for maintenance?

The hard drive of my laptop died, the manufacturer wants me to send it so that they can investigate, but I'm concerned that the drive might contain sensitive information. When I say the drive is ...
83
votes
7answers
14k views

Is CRT degaussing really dangerous for nearby laptops?

I have an old CRT connected to laptop as a secondary display. As you know, when CRT turns on it degausses itself; remember that sound when you turn it on, or force degaussing through menu. CRTs ...
83
votes
6answers
13k views

How is the capacity of a harddisk faked?

I was reading about magical Chinese drives. How would this be done? The post talks about a 'looped mode' and comments suggest having a different controller to lie to the OS. I went and bought one of ...
80
votes
5answers
275k views

How can I move the page file to another physical disk location?

I would like to know exact instructions for moving the page file from 1 disk location to another disk in Windows 7. I.e. from an SSD to a non-SSD drive. I've spent about two hours searching - Google,...
76
votes
4answers
5k views

Why does performance of a regular hard drive decrease over the duration of a benchmark while SSD doesn't?

I use HD Tune to measure performance of the hard drive. The tests typically take 2-3 minutes and the transfer rate of a regular hard drive decreases dramatically as the test comes to a close. ...
71
votes
6answers
135k views

Why is CBS.log file size 20 GB

Two days ago I had a full C: drive, after which I deleted 8 GB of data. The next day the hard drive was full again, so I continued with deleting another 5 GB, and once again the next day the disk was ...
70
votes
3answers
9k views

Why are smaller capacity SSDs slower?

I was reading this Tom's Hardware article on testing SSDs and came across the following claim: With SSDs, performance varies by capacity point. Smaller drives tend to be slower than larger ones, ...
61
votes
14answers
8k views

Is there a way to make my hard drive inaccessible to everyone but me?

Let me give you some backup story first: A computer technician challenged me to give him my laptop and ask him for any piece of information that I wanted to "hide" in my hard drive. He claimed that he ...
59
votes
9answers
39k views

Does vertical position affect the lifespan or integrity of a hard drive?

I've noticed on many small PC cases that the hard drives are installed vertically. In midi cases, towers and others of a larger housing, they are in the horizontal position. What impact on a hard ...
58
votes
11answers
125k views

Free way to clone HDD to SSD?

Is there a free way to clone a full Windows 7 installation from HDD to SSD? (The free part is important, I know I can pay for Acronis True Image.) SSDs are usually much smaller than HDDs which ...
58
votes
10answers
159k views

How to check the health of a hard drive

My SATA drive started clicking and I was unable to access the data. It was not clicking loudly though, like a drive that has already gone bad. After tightening the connections to the hard drive, it ...
58
votes
9answers
214k views

Windows 8.1 Update 1 Disk Usage 100%

Background Information / Computer Specs I have a 14-inch Samsung Series 5 Ultra. Core i5 CPU, 750GB HDD, 8GB RAM, Intel HD Graphics 4000. I've had the computer for about 1.5 years with no major ...
53
votes
7answers
6k views

Commuting with a laptop that is powered on

How safe is it to leave my laptop running a build or other time-consuming task when I am traveling? I mostly travel on a two-wheeler, with my laptop in a backpack, strapped vertically to my back (left ...
52
votes
14answers
16k views

Why are they putting “processors” on hard drives?

What does it mean when hard drives have a processor on the hard drive? How does it work, and what benefit does it have? I don't understand - the CPU on the computer is the processor and the hard ...
47
votes
9answers
78k views

How can I use my small SSD as a cache for a larger hard disk?

I would like to use a (small) SSD disk as a cache for a large hard disk. I realize there are hardware-based products that do this: HighPoint RocketHybrid HBA, Intel SmartResponse and others. There is ...
46
votes
8answers
158k views

Extremely high disk activity without any real usage

In a nutshell, the problem looks like this picture: In short, gigantic latency, very slow read speed (I assume that is caused by the same thing). After a very very painful few minutes, everything ...
45
votes
5answers
9k views

**How** harmful is a hard disk spin cycle?

It is conventional wisdom¹ that each time you spin a hard disk down and back up, you shave some time off its life expectancy. The topic has been discussed before: Is turning off hard disks harmful? ...
43
votes
7answers
63k views

Is turning off hard disks harmful?

I set Windows 7 to turn off hard disks after 20 minutes of nonuse, which it does a really good job at - it seems to turn off individual hard disks that have been idle for 20 minutes exactly. When I ...
43
votes
4answers
24k views

How does NTFS compression affect performance?

I've heard that NTFS compression can reduce performance due to extra CPU usage, but I've read reports that it may actually increase performance because of reduced disk reads. How exactly does NTFS ...
42
votes
19answers
19k views

Destroy a hard drive without proper equipment

I need to make two hard drives unreadable. Unfortunately, I have some constraints which make this harder than usual (in particular, they rule out the answers to other questions): I don’t have a ...
42
votes
1answer
34k views

What is the purpose of this 4-pin interface on SATA HDDs and why doesn't it exist on SSDs?

I have 4 HDDs here with me, from 3 different manufacturers, and all of them have the following 4-pin extra interface beside the SATA connector: Looking on internet, I can see that it exists on all ...
39
votes
14answers
70k views

Easiest way to move my Windows installation to an SSD?

I've taken the plunge and bought an SSD and want to move my existing Windows installation over. The current hard disk is 500Gb, but I've trimmed the contents down to about ~40Gb. I'm transferring it ...
38
votes
4answers
4k views

Linux is to mount as Windows is to _______?

So Linux "mounts" a hard drive to perform some operation such as reading/writing. Does Windows "mount" in the same way? Is it called something different in the context of Microsoft?
38
votes
6answers
45k views

How do I determine whether a drive is an HDD or SSD in Windows 8?

I've recently received an assembled PC. I don't know if the disk is an SSD or old HDD (whether SATA or other technologies). I can't find a way to tell if the disk is SSD or not, apart from the size ...
38
votes
3answers
5k views

Why does my SSD internally encrypt data, even without a password set?

Recently I had an SSD fail and am attempting to do a data recovery. The data recovery company tells us that it is complicated because the build-in drive controller uses encryption. I presume this to ...
38
votes
4answers
22k views

How badly do SSDs degrade without TRIM?

SSDs have been out for a few years, and have seen all kinds of usage patterns. Windows and Linux support the TRIM command, with Mac OS still trailing behind here. Update (2011): It appears OSX Snow ...
38
votes
1answer
86k views

What does “LFF SATA” mean?

I've heard of SATA, but "LFF SATA" as listed on HP's specs page is a new one for me. What does the "LFF" bit mean?
37
votes
9answers
37k views

How much time until an unused hard drive loses its data?

Do you guys know how much time needs to pass until the data stored on a hard drive starts to degrade? To keep the data intact for long periods of time, I heard you need to periodically rewrite it on ...
36
votes
2answers
14k views

How vibration sensitive are hard disk drives?

I've gotten my hands on a seriously cheap laptop grade 2.5 inch drive. I'm intending to use one on a desktop that doesn't have 2.5 inch bays as a boot drive. While I know there are adapters available, ...
36
votes
4answers
6k views

When to stop using a hard drive? What rules/software apply?

When having a old hard disk - when should you stop using it ? I recently got a new 1 TB hard disk, and am left with 3 old hard drives (320 GB, 250GB, 160 GB). I am now wondering which of them to ...
35
votes
4answers
4k views

Why do HDDs mostly have the same speed as 5400, 7200, 10000 RPM?

Why do hard disk drives mostly have the same speed? They are mostly 5400, 7200, 10000 RPM. Why not 6000 or 8000? Is there any reason or benefit for having those speeds?
35
votes
5answers
56k views

Good block size for disk-cloning with diskdump (dd)

I use dd in its simplest form to clone a hard drive: dd if=INPUT of=OUTPUT However, I read in the manpage that dd knows a blocksize parameter. Is there an optimal value for the blocksize parameter ...
35
votes
5answers
72k views

Why should I choose (or not) AHCI over IDE in my PC's BIOS settings?

I've noticed in the BIOS settings of the newer PCs I own that I can configure the drive controller work either in AHCI (Advanced Host Controller Interface) mode, or else in IDE mode. I'm suspecting ...
34
votes
7answers
29k views

Why is my computer really slow despite having a considerable amount of free memory?

I have a Lenovo g560 3-4 years old, Intel i5, with 2GB ram and with a Geforce 310M. It always had some issues during startup or when starting a new program, but recently it just went crazy. From the ...
34
votes
4answers
31k views

How do I find out what processes are accessing the hard disk in a GNU/Linux-based system?

I'm looking for the equivalent to top for disk access, so I can tell which process(es) are currently reading and/or writing to disk. I'm currently using Ubuntu, but I imagine there's a standard tool ...
33
votes
8answers
7k views

Is flash drive wear a significant issue?

My netbook has a flash drive instead of a hard disk drive, and I'm using Ubuntu Netbook Remix with ext3 as the file system. I've read some articles concerning flash drive wear, and the main concerns ...
33
votes
4answers
40k views

Windows Disk I/O 100% at boot for 20 Minutes

I have a fast computer (quad-core i7, 3.5 Ghz, 24 GB of RAM, Windows 8.1) and I installed a new hard drive less than a year ago that was supposed to be as fast as you could buy for an HHD and not an ...
32
votes
7answers
180k views

What are the differences between 2.5“ and 3.5” hard disks?

What does the 2.5"/3.5" value indicate? The thickness? I want one of my friends to buy 1TB hard disk for me. I know I want a 1TB capacity and 7200rpm, but don't know how to choose between 2.5" and 3....
31
votes
5answers
34k views

How Do I Find The Hardware Block Read Size for My Hard Drive?

I'm trying to figure out the optimal size for a large copy from my hard drive using dd. I'm trying to figure out what the best blocksize to use it, which I would assume is the hardware block size for ...
31
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5answers
50k views

why does the partition start on sector 2048 instead of 63

I had two drives partitioned the same and running 2 raid partitions on each. One died and I replaced it under warranty for the same model. While trying to partition it, the first partition can only ...
31
votes
6answers
27k views

How can I log my hard drive activity by program?

I am using Windows XP and am looking for a utility that can tell me the percentage of hard drive activity a program is using. Basically, I'm looking for something like Task Manager and its ability ...
30
votes
9answers
15k views

Do hard drives really have open cases now?

I'm shopping for new hard drives and all the stores (Amazon, Overstock, Newegg, etc.) now show product pictures like this: I can find no information in the product descriptions or in Google searches ...
30
votes
10answers
9k views

Determining if a hard disk has been removed and data copied from it?

Is there a method or a tool that can detect if someone has separated my hard disk from my computer, copied data from it, and returned it back? I want to be sure that no one has done this without my ...