They may be DIMM, but they have fans
Subject: Memory | August 4, 2009 - 05:57 PM | Jeremy Hellstrom
It is a good thing that the Core i7 memory controller limits RAM voltage to 1.65V, otherwise you would never fit anything on a motherboard save your DDR3 DIMMs, the heatspreaders that are attached to the ICs and the fan assembly needed to cool them. As it is, once low latency DDR3 hits the 1600MHz mark, the cooling apparatuses take up enough space that case choices and CPU heatsink choices are affected by them. For instance the Kingston Hyper X DDR3-1600 @
9-9-9-27 Triple Channel kit comes with heatspreaders that more than double the height of the DIMMs and a nice shroud and fan assembly. Find out how well they will help your overclocking potential at Overclockers Club.
"Since the modules are rated at 1600MHz 9-9-9-27 what better place to start then to see
if the loose timings can be improved upon. To start with I lowered the Cas Latency,
TRTP and TRD to 8 and the TRAS to 24 all while running the default 1.65 volts.
Expecting a black screen I was surprised that the modules booted and then tested fine
at 8-8-8-24. Next I started bumping the memory speed up by increasing the bclock a few
MHz at a time and rebooting. Then thing is the modules kept scaling with the 8-8-8
subtimings until I reached 1884MHz. So far 284MHz worth of extra clock speed. At this
level I was able to benchmark game and run stability tests at will. Any higher though
required the Cas Latency to move to 9. Voltage did not help and above 1.68 I would get
errors so the max voltage used was 1.67 volts. Moving on up from 1884 I finally reached
1976MHz with the timings at 9-9-8-24 with the memory voltage at 1.66 volts QPI volts at
+220 and the CPU at 1.28 volts. 376MHz (187MHz actual) worth of increase for a set of
memory that costs just 131 bucks is nothing to sneeze at. Unfortunately 2000MHz just
was not to be for me on this set. So close yet so far."
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