I have been promising a RAM overclocking guide for seemingly forever so I've got
the Kingston hyperx blue 4 gig kit of DDR3 memory on my test bench today uh in
addition to that I do have a hyperx RAM fan which I did an unboxing of a while
back I found it to be extremely high quality I really like the look of it
overall and the other relevant things that I have today on my test bench are a
core i7 875k unlocked CPU so that's
what's going on under the hood over here and then I'm using a p7p 5de premium
motherboard in case you are wondering so the first thing we're going to do today
is we're going to get everything set up for a baseline reading so that means
I've got my CPU set up at stock frequency and I've actually turned off
turbo mode so we are just going to be running it at peer stock frequency this
is going to allow us to see exactly what
impact just changing the memory has on an otherwise completely stable Baseline
system okay the other thing that I've done is I've enabled the XMP profile for
this memory so that goes ahead and changes all the memory timings for me
Isn't that handy U make sure you buy memory with XMP if you don't want to
fuss around with all of this stuff so it goes ahead changes the frequency to 1600
MHz changes the timings to 9927 these are your primary timings the
most important one is this one right here that is the Cass Cas latency so
here this frequency that is the speed of the memory so that how how fast it
Cycles around these ones are the delay
so higher this and lower this is always better 1 n or 1 t or 2 N or 2T that's a
secondary timing that does have an impact on performance as well and then
these voltages that it's dialed in for me 1.65 that's the memory voltage and
1.3 that is the voltage of the integrated memory controller on the CPU
you should be aware that with core i7 and core i5 CPUs you should never go
over 1.65 volts on the memory because you can damage the memory controller
that is built into the CPU so we're going to go ahead take some baseline
readings and then we're going to come back and play around with some of these settings a little bit and see how much
more performance we can squeeze out of this memory now that we've got the RAM
dialed into our stock XMP overclocked
profile you can see here all of the settings are correct and the CPU is
running at its stock frequency we're just going to take a couple of
benchmarks as a base line here so Super PI is a popular memory Benchmark because
what it does is it gives you uh probably
the largest possible separation between
uh like minute setting basically it's it's a very very fine way of measuring
the the performance of the CPU and RAM
and it'll give you differences that you otherwise wouldn't be able to measure so
you can figure out if what you're doing is beneficial or not so you can see we
calculated pi to 1 million decimal places and we end up with a result of
zooming in so I can see oh no that's not right Calculate 1 million decimal places
it's giving me the wrong one here so now click to start okay and let's find out
what we get this time and we're going to take a quick 3D Mark reading as well and
then we're going to come back to these benchmarks once we've played around with
the frequency latencies of the memory and we're going to see how much we are
able to improve our system performance so there there's the real value is
14305
seconds all right so we're going to run 3D Mark and then I'll be back in a
minute once that's done so there you have it our Baseline
3D mar06 reading is
18534 so 1
18534 3D marks it should also be noted I
am running these benchmarks with turbo mode disabled on the CPU so it is
running only at the default CPU multiplier of 22x it is not scaling up
when I run intensive benchmarks this is just to isolate the RAM as the
performance variable that we're looking at today so the first thing we're going
to try today is leaving our timings at default leaving all the voltages the
same cuz we don't really want to that's outside the scope of this particular
video we don't want to Tinker around with those and what we're going to go
ahead and do is take the CPU ratio and turn it down so we're still very close
to the 2.9 926 Target CPU frequency and
then we're going to turn up the base clock now turning up the base clock is
going to give us a bit of a boost at equal frequency on the CPU and then it's
also going to give us at the same DDR3 speed so go I'm going to go ahead so 146
is where I'm headed so 133 is stock you can see at 133 the options I have are
all of your standard DDR3 speed options but as soon as I go up to 146 that 1600
MHz option turns into 17 50 so we're going to go ahead and see if
we can boot up at these speeds and if we are stable and what kind of performance
impact that's going to make okay I've done some tinkering around and staying
within the same CPU frequency range so about 2.93 GHz I have found that the
highest I was able to go was by lowering the CPU ratio to 17x and increasing the
base clock to 172 so this gives us a DDR3 speed of 2.06 4 GHz the RAM was
stable at this speed so we're going to take some more benchmarks and we're
going to find out what we gained by increasing the memory speed to 2 GHz now
one thing that I do want to point out is that you do not have to run the CPU at
stock speed in fact there's probably more benefit to overclocking the RAM
when you're running an overclocked CPU because the CPU needs more data to keep
it fed but the reason that I did it this
way is because what you'd normally do is find your max CPU frequency in this case
I'm I'm pretending my Max CPU frequency is stock speed so You' find your max CPU
frequency and then you'd tune the RAM from there so uh once you by the time
you're tuning RAM you're already trying to stay within kind of a a fixed range
of CPU frequencies so we'll go ahead fire up CPU Z fire up Super PI so you
can see we're running our CPU at stock speed our RAM is now running
substantially faster this is 1/ half of the actual data rate because it is uh d
DDR class of memory so we're running
start to calculate to 1 million decimal
places so here we are we've seen a
25% increase in RAM speed and let's see
how much of a speed increase we will gain from that so
14.22 7 is our new super
pie 14.22 7 is our new super pie score and
then we'll go ahead and have a look at the 3D Mark score in a moment so we end
up with a score of 18692 which is a slight boost over what
we were recording as our Baseline although it's pretty much within the
margin of error uh so the overclocking method that we used today was just
increasing the RAM frequency uh we found it didn't have much of an impact but
look at it this way you buy the hyperx blue and obviously your results May Vary
you can get upwards of a 25% increase in
speed over what it's actually rated for which even if it only gives you like a
1% increase in a couple of the programs
you use it is a free increase nonetheless so we're going to see how
low we can go with latency overclocking and see if we can get some bigger boosts
that way stay tuned for more by simply adjusting the latencies we were able to
go from 999 27 latencies all the way
down to 77720 you consider the cost difference between kits that are
otherwise basically identical so you look at kits like this where it's a 4
gig kit uh 2x2 GB DDR 3600 and cl9
versus cl8 and you see upwards of a $20
price Delta well it starts to make uh like an overclocking friendly kit like
the blue that we're using today look like a pretty good value if you can get
all of that extra Headroom out of it so let's have a look at our super pie
calculation for our uh 7
overclocking in this case a latency reduction more than like increasing the
clock speed overclocking so it's a little bit different okay so we see a
score of 14
point no I missed it okay we'll try
again I apologize for that I guess I could in theory have just turned off the
camera and gone back and read it but um
I didn't think of that until now and the camera's been running so we might as
well roll with it okay so 14.29 that
seems a little bit higher
290 okay so I'll run my 3D Mark Benchmark and then I will be back in a
moment okay well at 18654 3D marks we don't see a huge
performance difference between our stock 999 27 timings and our tightened up 7
7720 timings uh but this has been my
DDR3 overclocking guide I mean if especially if you're done overclocking
your CPU because that's where you'll see some big performance gains and you want
to Tinker with it a little bit more I highly encourage you to go ahead try
overclocking your memory uh don't forget to do stability checks though all along
the way when you're doing any overclocking and bear in mind of course
that my results today are not necessarily reproducible if you buy the
same RAM I was lucky enough to get A2 5% overclock in terms of frequency or a
significant uh two speed grade uh bump
down in latency so Improvement in latency uh but you may not have the same
results so the best way well not the best way but the way that I use to uh to
check if memory is stable is I use prime 95 blend I use a custom one and then I
go ahead and let it use all or most of
the memory I have installed in the system so as long as this doesn't crash over a period of 8 to 12 hours you you
can assume that your RAM is pretty much stable and then that way even if it's
only a small Improvement you can have some performance Improvement so thank
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