I would leave it as it came to me, unless I had special needs, then I would change it.
I do not believe that in this situation that any speed difference could ever be seen between the two different settings, even after advanced benchmarking repeatedly and averaging the results.
SATA Hard Drive Jumper Settings WD SATA
WD SATA hard drives are factory set for workstation/desktop use. For
enterprise storage requirements, the jumpers can be set to enable
spread spectrum clocking or power-up in standby modes. WD SATA drives
are shipped from the factory either with or without a jumper
shunt in the spread spectrum clocking (SSC) enable/disable position
(on pins 1 and 2). It is not necessary to add or remove the jumper
shunt on the drive for workstation/desktop use. For enterprise
storage enviroments, use the following advanced settings:
SSC Mode (Default 1): spread spectrum clocking feature enabled or
disabled. Default 1 setting is disabled or jumper shunt placed on
pins 1–2. Removing the jumper enables the spread spectrum clocking
SSC Mode (Default 2): spread spectrum clocking feature enabled or
disabled. Default 2 setting is disabled or no jumper shunt placed on
pins 1–2. Adding the jumper to pins 1–2 enables the spread spectrum
Who writes this stuff! I still cannot read it the way it is in the original document (last sentence looks incorrect)... Put the jumper on 1-2 to disable SSC Would that be so hard to say?
In rare situtions where there might be a frequency issue based on country, with stuff similar to this (not nessiarily this) they will often ship to that country with it set to work in that country or location.
G5 Mac Issue with SSC
Last week there were several posts on problems with SerialATA hard
drives with SSC (Spread Spectrum Clocking) enabled when using the
onboard G5 SATA and with some (not all) Mac PCI SATA cards.
. . . . . . . . . . . . . . . . . . . . . . . . . . . .
We and Firmtek have found problems with certain SATA drives which have
SSC turned on and therefore will NOT work
Users thinking thier Seagate hard drive is Dead or DOA in situations, they used a Segate utility to disable SSC.
and the opposite apparently:
Some users have been using other brands of HDD’s (in RAID
configurations) on the Intel Matrix Storage with the ICH7R on the 945
and 955 chipset and have reported that the system crashes during the
installation with a BSOD. They have blamed the motherboard and memory
but this is not the case. This is because SSC is disabled on the HDD.
It seems as if all the controllers that have problems with SSC-enabled
drives are RAID controllers