This summer, when I first started assembling my HTPC, I used the parts I had at home and bought what was missing. So in my ATC-620 case, I ended up with my old friend, a Seagate Barracuda IV 40Gb. Very quiet, with temps at around 36C to 39C (idle to full speed, ambiant 25C).

I then wanted more room, so I swapped it with a brand new Barracuda V 120Gb. Maybe a little more seek noise, but barely. But temps rose to 40C-44C.

And last week, I won (lucky me) a Samsung Spinpoint SP80 80Gb HD at a local computer shop. Swapping it again, I was impressed. I can't hear the drive at all. And the best thing is that my temps now stay between 33C and 35C.

Same case, same airflow, same ambiant. Real big diff in temps.

Lascap

Your temps are almost exactly the same as my temps for all those same drives (except the Samsung is a 160GB version).

Are those temps as reported by each drive's SMART? If so, do you have any other case/cpu temps that also show variation?

(The real question - varying SMART temps could be because of the location of the sensor and the firmware producing a number. If a Samsung really is cooler then maybe you can see the effect elsewhere as well?)

Yes, readings comes from smart and SpeedFan v4.09

Case temps, as well as CPU temps, pretty much stay in the same range, whatever the HD. Case overs between 37C and 40C and CPU is between 41c and 45C.

After removing the Barracuda V from the CoolerMaster desktop case, I installed it in an Antec SX-600 mid tower case. Humming now around 36C for the HD and 37C for the case. That's about 2 more degrees than the Barracuda IV. Maybe the B-V needs more airflow to cool effectively? (didn't try the Samsung in the tower case)

Lascap

Wow, that's an enormous difference. No idea HDDs could produce that much heat. Thought heat was chiefly from CPU/GPU/PSU

I run 4 80GB drives in my server, all 5400rpm. An older Seagate U6, and three Samsung drives (~1 year old, so 40Gb per platter). I don't often feel to see how hot they get, but I have a 7V (or it might be 5V) 120mm fan in front and they barely get any warmer than the ambient. I used to buy Fujitsu's for reliability, speed, noise and heat. Now its Samsung, and they're well priced as well.

On reflection, we need to be careful of the conclusions we can jump to.

Even if the SMART temps are measured at the same place and converted to a number with the identical algorithm, they are not THAT different. And in reality typical drive power consumption is around 10W which can affect the environment in the case, but is only around 10% of the total. In general I figure worrying about how much the hdd heats my case (I think I started it ) is OTT. Probably more relevant is how well engineered the drive is to disperse that 10W, and the DeathStars may be proof you cant always trust the manufacturer? But from this angle it is worth having some airflow around our hdd.

OTOH, the datasheet numbers for a Samsung I looked at (SP0812C) are lower than a Barracuda sheet I have (7200.7)
Seek 9.5W v 12.5W
Read/write 8.5W v 12W
so it is true (at least on paper) there are a couple of Watts to be saved.

See also the Barracuda review by Dru for reference/the difficulties of subjective heat.

{My real contribution is that I recently upgraded a mobo. Same CPU/speed/VCore/hs/fan/case/ambient but the reported CPU temp is up more than 10C. My assumption is that the temp is probably unchanged, but the sensor & BIOS conversion of R to an number is actually making the difference. So reported temps deserve some understanding/analysis.}

Dukla - is their any temps we should really be afraid of approaching, I know their are specs for each hard drive, but is their a general area where we need to attach a fan to blow on the hard drive?

I really don't know - I can't even start to claim expertiese in this area.

My guesses/instincts say e.g. the 7200.7 spec has an operating environment max of 60C. So that must mean the hot parts of the drive will be even hotter than that because of the extra heat it generates itself (Seagate say 69C). So (according to the spec) a SMART temp over 60 is not in itself cause for alarm. Based on my lack of trust where the SMART sensor is, and how it is converted to a number, I would be really unhappy to see SMART reports over 60C. Based on wisdom that lifespan of electronics deteriorates with higher temps I would much prefer a well ventilated hdd and a SMART temp no more than about 5C above ambient. (My 7200 currently reports 22C, room temp is 20C ) For a device dissipating 10W this should be a fairly 'easy' design spec. For a less well ventilated hdd 10C above ambient is unlikely to be of any harm. But exactly because it is heat generating I figure hdd do deserve some airflow. I am less worried about my optical drives as 99% of the time they are idle.

OTOH, dont forget the temp gradient: again the 7200.7 spec says max 20C change per hour. I would figure, as these things are (also) mechanical to pretty fine tolerances, temp changes are probably more harmful than the absolute temp.

Thanks Dukla, I am still fidgeting with my maxtor whether to bottom mount it? or just blow a 80mm L over it and leave it in the upper drive bay, I barely stay under 40c at idle and easily go to about 41 to 44c when gaming, that is even with winter onset here in the US. {:

Figured it was worth updating this thread: further to my preferences about 5 or 10C above ambient I am bemused to see my Dell laptop SMART running about 30C above ambient. (Room temp is office, I guess 21C, SMART is reporting 51-54C!).

Also figure while I am at it to link to this thread specifically considering hdd temps.

i guess the 30's is best place for hd run at

I use the Samsung 160GB disk and have out an external temp probe on it. I find tha the SMART temp value is indeed different. You would expect this as my probe is on the base of the spindle support part of the drive and I have no idea where the SMART sensor is.

At low temps of 14C I get a difference in readings of about 4 degrees with the proble saying 18C and Samsung sating 14C. As the drive warms up more and more and the heat districution becomes more even then the two start to match although the probe is always a bit hotter.

Right now DTEMP is giving me 25C for the Samsung but the probe says 26.0.

Lone Ranger

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If you are interested, the ambient room temp is approx 20C and the drive is placed on its smallest end at the bottom of the PC case. I have deliberately left the case open and also put a piece of card between the case fan and the drive in order to see what temps the drive gets to.

However I am sure that there is still going to be some air flow from the fan over the drive.

My Barracuda IV in the same case but mounted higher and with relatively poor ventilation flow shows 33C while my Barracuda V on the bottom of the case next to the Samsung shows 30C.

I bought one of those Seagate U6s as a data storage drive last year because they spun slower and so I figured they would be cooler than the Barracuda. And that turned out to be the case but they are not as cool as the Samsung 7200s.

You mean under the motor, yes? A picture would be nice...

What type of thermistor do You use? Flat one, or some other kind?

The only reference to measuring drive temperatures w/ external sensor which I've seen was on Seagate 15K.3's datasheet. The "right" spot to measure is above the connectors, in the middle of the "chassis" of the drive (the metal part).



Today as I booted my computer (been off nearly two days), with ambient 20°C, I measured the SMART temp of 17°C as I got to the desktop. The drive's temp rose to 19°C, stayed there for 3-4 mins, then dropped to 15°C for one minute (notice that most software measures drive temps only every minute) and then rose to 17°C (2-3 min), and then back to 19°C (one min).

Then it dropped to 18°C, was there for 2-3 mins, then jumped to 25°C! After that the temp rises two degrees at a time, and after 90 mins, temp is now 31°C. As I've mentioned earlier, the drive shows only odd values, except before the jump. Internal calibration perhaps?

I've turned the computer off few times to remove/attach a HD (I have a Kingwin rack), which takes like 30 seconds. When I boot back to Windows, the drive's temp is much higher than it was when I shut down. I'd say at least 4-6 degrees, but I can't remember exactly. After a while (say, 15-30 mins) the temp gradually drops to the level before the shut down. Rebooting doesn't produce this effect. I think that the drive calibrates the sensor if the drive is unpowered.

BTW, SpeedFan 4.09 has a graph feature, which is quite nice for following temps over time.

Cheers,

Jan