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Shield your sata cables!

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Frosty_47

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I apologies in advance for making such a rude post however, I just can NOT BELIEVE the difference Shielded SATA cable makes! I assembled a new system with Western Digital 1TB green HDD. I was getting 1.6mb/s read on average that took like 3 mins for my system to boot. I thought I got a bad drive however, after I wrapped the cable with aluminum foil tape, and attached a grounded wire to it, my HDD performance sky rocketed! My read speed reached over 90mb/S on average!
So Please shield and GND your SATA cables! It made a hudge difference for me!

it only costs like $2 to do it.

I recommend you use HD_Speed a free utility to test your hard drive performance. You can get it here:
http://www.steelbytes.com/?mid=20

I should post a youtube video of this someday :)
 
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Weird. My system does that without (as far as I know) shielded cables. WHy is the EMI in your system so bad? I use multiple 1TB Samsung Spinpoints and 1TB WD Caviar BLacks.
 
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Strange result. Your should have higher data transfer rates with unshielded cables. There is a possiblity that by adding shielding it corrected a open cable
 
Strange result. Your should have higher data transfer rates with unshielded cables. There is a possiblity that by adding shielding it corrected a open cable

That makes no sense. Why would you get better perfomance with unshielded cables? I mean with a lot of noise your HDD has to resend the curuptted data and that reduces perfomance.
 
Unless your SATA cables are really long > 18" or you have a particularity noisy motherboard there should be no difference between shielded and unshielded as SATA uses differential signaling.
 
Weird. My system does that without (as far as I know) unshielded cables. WHy is the EMI in your system so bad? I use multiple 1TB Samsung Spinpoints and 1TB WD Caviar BLacks.

My asumption for having so much noise is due to the bottom placement of PSU. The power cables run right next to SATA PORTS and SATA cable sits right in between all the PSU cables.

Also I have five 120mm Fans, one 140mm Fan, and two 92mm fans.
 
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Unless your SATA cables are really long > 18" or you have a particularity noisy motherboard there should be no difference between shielded and unshielded as SATA uses differential signaling.

I think they are 12" long
 
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I assembled a new system with Western Digital 1TB green HDD
If it's speed you wanted those are slow ie Green drives, the Black series is faster.
https://techreport.com/articles.x/15769

At 12" it's all in your imagination. No difference unless the old cables were crap.

Plus the 1TB WD Green had two versions, the first was really slow the second much improved. Want something fast, try an SSD or Raptor.
 
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Better Performance with Unshielded cables.

In most cases an unshielded cable has a higher impedance than an equivalent sheilded version. This higher impedance allows for higher frequency transmission and longer wire length.

Also as noted above differential signaling does not require shielded cables. External SATA cables tend to be shielded, however, this is to limit emiisions not to reduce noise picked up by the cable.
 
Better Performance with Unshielded cables.

In most cases an unshielded cable has a higher impedance than an equivalent sheilded version. This higher impedance allows for higher frequency transmission and longer wire length.

Also as noted above differential signaling does not require shielded cables. External SATA cables tend to be shielded, however, this is to limit emiisions not to reduce noise picked up by the cable.

How does a shielded cable have lower impedance?
SATA Frequency is fixed at 100Mhz. So what higher frequencies are you talking about?

EMI generated from high current PSU cables is far greater than EMI from a very low power SATA cable.

SATA II Cables and connectors are supposed to be shielded anyway. However, motherboard manufacturers along with the cable are to cheap to do that so when they advertise "SATA II" they mean their products are SATA II compatible but NOT SATA II certified. Hence this is probably the cause behind performance degradation.
 
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If it's speed you wanted those are slow ie Green drives, the Black series is faster.
Western Digital's Caviar Green hard drive - The Tech Report - Page 1

At 12" it's all in your imagination. No difference unless the old cables were crap.

Plus the 1TB WD Green had two versions, the first was really slow the second much improved. Want something fast, try an SSD or Raptor.

You are off topic. I was not discussing Hard Drives, I am nearly pointing out the problem with unshielded SATA cables. All my cables are brand new and came with my ASUS M4A79T DELUX motherboard.

Oh, and I would not buy a RAPTOR even if I could afford one because it's like running an air-compressor in terms of audio noise.
 
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Well either your old cables were defective or your testing methods are flawed. Do you have any 3rd party data (ie online reviews) that verify your claim.
Once upon a time some audio types were convinced painting green magic marker around the edge of a CD improved the sound. Of course test equipment (or double blind test) could not verify any difference in sound.
Green, water-based acrylic paint for coating the edges of CDs. The green color, which PvW [Peter van Willenswaard] found absorbs the laser's infrared wavelength, is presumably significant, but at present we have no idea why this tweak should so improve the sound of CDs. That it does so, however, seems to be beyond doubt to anyone with ears to hear (though no one single product has raised greater guffaws from the mainstream press). "This stuff works!" report JE [Jack English], PvW, and JA [John Atkinson], all of whom feel that it increases soundstage definition, improves the solidity of bass reproduction, and usefully lowers the level of treble grain so typical of CD sound. PvW and MC [Martin Colloms] report that a water-based poster pen, the Uniposca from Mitsubishi, has a very similar effect. MC also notes that the CD should rirst be destaticized and its edges degreased before the green paint is applied. (Vol. 14 No. 11, Vol. 19 No. 10; see also DO's [Dick Olsher] and TJN's [Thomas J. Norton] WCES reports in Vol. 13 No. 3, ST's [Sam Tellig] and RH's [Robert Harley] articles on CD tweaks in Vol. 13 No. 5, and "As We See It", Vol. 18 No. 7).
They even mention a particular magic marker!
An Eberhard Faber Design Art Marker No. 255 Amazing! Of course it's all bull....
snopes.com: Green CDs
 
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Are harddrives really that loud? I hear people talking about that a LOT. Changing the setting on my two 120mm fans at from medium to low reduces noise way more than the difference between harddrives, and even at low setting the harddrive noise is still the dominant noise source. Who would give a crap about harddrive noise? (Yes, my fans are very quiet at low speed setting).
 
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Well either your old cables were defective or your testing methods are flawed. Do you have any 3rd party data (ie online reviews) that verify your claim.
Once upon a time some audio types were convinced painting green magic marker around the edge of a CD improved the sound. Of course test equipment (or double blind test) could not verify any difference in sound.
They even mention a particular magic marker!
An Eberhard Faber Design Art Marker No. 255 Amazing! Of course it's all bull....
snopes.com: Green CDs

Why are you comparing some BS rumor that some individual came up with so he can sell idiots "magic markers" to something that makes perfect sense in terms of EMI suppression?

Oh and my SATA cables are brand new out of the box.

simple EMI control (check the graph and u will see 50db+ attenuation at 100Mhz)
https://multimedia.3m.com/mws/mediawebserver?66666UuZjcFSLXTtNX&VmXs6EVuQEcuZgVs6EVs6E666666--
 
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Rip up photo of SATA cable is attached
if the shield strip is broken perhaps it might misbehave.Perhaps external shielding might have helped Frosty_47.
 

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