Hard drive problems

UltraMan · 01-22-2002, 01:57 PM

Lately my carputer has been restarting itself, seemingly randomly. I brought it inside to troubleshoot, and when it is running at any kind of angle, it will restart itself. I think the drive may have gotten damaged in my truck.

I had it mounted vertically, although it was sitting at a slight angle in the truck.

Would i have better luck with a laptop drive and springs or some sort of a suspension around the drive? Thanks for any help.

LordMundi · 01-22-2002, 03:13 PM

I think you will have more luck mounting the drive horizontally... that way the bumps don't throw the heads in other places... I changed mine and found that it was much more robust against the bumps in the road. But if your puter is restarting, you may not have a HDD problem. It sounds like either a wire is loose and is resetting the motherboard. (Even a wire that doesn't go to the motherboard could cause that). If not these, you may want to check heat problems next.

Aaron Cake · 01-23-2002, 08:48 AM

I doubt it's a hard drive problem. Probably a loose card, bad connection, or cracked motherboard. Boot up only the motherboard, then flex it slightly and see if it reboots.

Do not use any suspension on your HD. Doing so will only cause more problems then it will solve (which several on this board have learned through bitter experience....including me).

MP3DUB · 01-27-2002, 02:17 AM

Quote:

Originally posted by Aaron Cake:
<STRONG>Do not use any suspension on your HD. Doing so will only cause more problems then it will solve (which several on this board have learned through bitter experience....including me).</STRONG>

I dont have any sort of shock absortion going on in my system, and being new to the forums, what problems have you had with the springs? the drive bottoming out?

brentp4 · 01-27-2002, 11:59 PM

Whoa whoa whoa..... Well.. then I have a question... I know this is going to sound newbie because I'm sure I could search and find it... and I will in just 2 secs.... But heres my theories....

My thought is that mounting the drive vertical would be much better. As with the way the arm moves over the platter... etc.... less chance of it hitting or the platter being bounce into the arm.

Also.... well hells bells... I don't know. I thought it would just be better to mount it that way for jitters and protection of the drive... Was thinking about doing something with tight springs or some firm rubber bands to allow just a little bit of give. say less than a half inch max. Oh well... I may ammend this in a few secs after searching....

~DD

brentp4 · 01-28-2002, 12:14 AM

Charles and Aaron.... after searching through the threads... I'd like to say your responses were the most helpful on this subject. Now I don't feel so worried mounting in vertically... because basically it sounds like it doens't matter.... hehe...

(Well i guess that search thing really works)

~DD

claylong · 01-29-2002, 06:13 PM

Aaron, what kind of problems did you have with the shock absorbtion on the HDD's? I am about to start my setup, and i was thinking of making provisions for shock aborbtion, but i do not see a reason to mount it vertically.

Thanks

UltraMan · 01-29-2002, 07:33 PM

This is very interesting. I have almost exclusivly been told that mounting the drive vertically is necessary. I am very interested in knowing what types of problems a suspension would present. As long as it dosent bottom out, it seems to be it could only be beneficial. Even if it didnt flex more than a half an inch, it would lower the forces down to acceptable levels. Most drives can take around 50 G's, and that acceleration is sustainable for only a millisecond or two on a very rigid surface. It seems that with tight rubberbands or stiff springs, it would work well.

wizardPC · 01-29-2002, 08:01 PM

I dont remember who said it, but I got this response when I asked this question as a newbie:

"Hard drives can handle 50-60 G's. If you are experiencing 50G's in your car, you have WAY bigger things to worry about than a hard drive failure."

UltraMan · 01-29-2002, 09:24 PM

Quote:

Originally posted by wizardPC:
<STRONG>
"Hard drives can handle 50-60 G's. If you are experiencing 50G's in your car, you have WAY bigger things to worry about than a hard drive failure."</STRONG>

I also heard this, and asked my physics teacher. He said that that type of acceleration is entirely possible. It comes from the deceleration, as in the floor moving upward from the shock absorbers after a bump, and the case of the computer falling downwards. When they hit, for a millisecond the rate of deceleration is very great, which is enough to cause a problem for the hard drive.

Aaron Cake · 01-30-2002, 08:26 AM

Shock absorbtion created more vibrations than it eliminated, resulting in the death of 3 hard drives.

Tremek · 01-30-2002, 01:38 PM

So you're saying that using something like bits of closed-cell foam on either side of a drive, or to mount the drive with something like rubber gromits is a bad idea? I had considered mounting the drive in my case vertically; using two rubber gromits at each mount with large screws isolated in the middle of it I was thinking that would isolate some of the harder shocks.

Not the case? I'm not talking about rubber bands, I'm simply suggesting the HD not be physically in contact with the case through screws.

KRIS3 · 01-30-2002, 02:28 PM

can some one with experience tell, it is better if the HD is on a shock absorbtion system or simply put some spongie foam on the sides and screwit to the case?

jshrieve · 01-30-2002, 07:20 PM

imo, mounting a drive vertically is bunk. If you need to put it vertically to fit it in your case, go ahead, but I don't think it's going to help your drive survive any longer.
I've had my hard drive mounted horizontally for a year and never had a problem.

As for suspension, I think the car's suspension + the trunk carpet liner (which has a very thin like of padding) is more than sufficient.

Having your drive's head skittered all over the platter surface because a large shock while mounted vertically isn't any better.

As for the Gs.. 50Gs is easy to come by. Dropping your drive on a stone floor from 6" can result in hundreds of Gs. Often HD damage comes from clacking two drives together during handling.

If you want your HD to last, do the one thing that's pretty much sure to help. Get a laptop HD. They're specifically designed to be tougher, to handle MUCH great shock (in the range of 4-10x, operating shock), wider temperatures and use less power. I use an IBM TravelStar drive.

JamesB · 01-30-2002, 10:35 PM

Have a look at the physics for a moment:

First, lets examine what kinds of forces are acting:

- critical vertical movement
- moderate horizontal movement
- combined creates torsional as well as diagonal movement

Now let's examine what the movement looks like in a typical "bump" environment. For test purposes, our point of observation will be earth (that is, we are observing from a fixed point without any motion)

as your car hits the bump (while moving at a fixed speed) .. here is the motion of the drive:

position on the y axis indicates height .. we will determine the position to start at time 0 (which is moments before the test subject will hit the half-sine bump. Notice that opposed to typical convention, a negative change in height is represented by the (positive) portion of teh Y axis

time on the x axis indicates an arbitrary time interval of < 1 s

If we examine (the crude) graph, you will notice that the test subject (harddrive) will initially move down to either the height of the bump .. or to the tensile threshold of the springs.

Furthering our observations, we notice that the motion completes a sinusoidal motion .. which creates a large problem for us.

Imagine now that at the furthest extent of the motion (at the crests) the hard drive has stopped accelerating and has stored a considerable amount of potential energy in the springs ... this will create a very large instantaneous acceleration in the opposite direction (the direction of the net force) ..

If we put some numbers in the whole scenario, we would realize that the inertia of the harddrive upon instantaneous acceleration either up or down is quite large .. and this presents a problem with the drive's internal mechanics. This goes back to the concept that objects at rest (or in motion) tend to resist change (ie. motion in another direction) .. thus causing stress on the parts ...

I realize that this is both long winded and a fairly crude explanation .. though I hope it helps all the same.