All about CPU
 Latest CPU articles
All CPU articles

Newsletters


  • Ask your question about IT issues
  • Post

Partners

The Games selection

adventure : Scoobydoo: Episode 2 The sequel of Scooby and Sammy's adventures. Same principle as in the previous episode (available on this website). Click on "Instructions" to see...
crazy : Xiao Xiao 7 A great fight scene from the animation movies Xiao Xiao.
Ads

Sponsored links

Making Lemonade: Overclocking Your Locked AMD Processor

2:00 AM - 08/27/2009 by Paul Henningsen

Readers of this site are probably well aware of the overclocking potential in AMD’s Phenom II processors. Through CPU reviews, performance comparisons, picture stories, and “How To” guides, Tom’s Hardware has highlighted the hidden potential within these processors and detailed how to attain similar results at home.

From our explorations of the AM2+ or AM3 platform, using basic or extreme cooling, the one constant has been the use of a Black Edition Phenom II—and for good reason. These “unlocked” processors are specifically targeted at enthusiasts who want to squeeze more performance out of the product than they paid for.

This time, however, we’ll specifically look into overclocking a “locked” processor. We chose the AMD Phenom II X3 710, a roughly $100, 2.6 GHz triple-core chip. Though it certainly doesn't lack stock performance or core speed potential, a locked processor such as this one offers far less overclocking flexibility.

What exactly is a locked processor? Specifically, we’re referring to the “locking” of the CPU multiplier and, in the case of this AMD processor, the CPU VID (voltage ID). Actually, both values can be reduced, but they’re locked from being raised above their stock base value.

Taking a look at the equation core speed = CPU multiplier x reference clock, you can see that eliminating the ability to raise the CPU multiplier means any increase in core speed will need to come from raising the reference clock. This will, in turn, raise the HT (HyperTransport) link speed, northbridge speed, and memory frequency, which are also based on the reference clock. If you need a refresher on terminology or calculations, take a look back at this How To: guide.

To cool our retail Phenom II processor, we set the boxed cooler aside and used the Xigmatek HDT-S1283. However, to have any hope of pushing this processor up into the same range as a Black Edition, we also needed a motherboard capable of running a high reference clock. As seen in this motherboard roundup, the MSI 790FX-GD70 stands out as a winner in this area and should allow us to push this CPU to its air-cooled limit.

In this story, we’ll highlight a few different methods of overclocking our locked processor, including conventional BIOS overclocking, AMD’s OverDrive utility, and the 790FX-GD70’s nifty OC Dial. We’ll walk through these three methods, comparing both the experience and results achieved. Finally, we’ll take a brief look at the performance gained by overclocking the CPU, northbridge (NB), and memory.


Talkback
stray_gator 08/27/2009 9:18 AM
Show
sohei 08/27/2009 10:56 AM
Hide
-13+

it's about how to squeeze all performance from an locked cpu .
this is a pro' article (head shot)

nzprogamer 08/27/2009 11:52 AM
Hide
-0+

im a big amd fans, good stuff here, look forward to go back to amd

amdfangirl 08/27/2009 12:50 PM
Hide
-5+

Good article! Too bad I killed my AMD CPU :P

brisingamen 08/27/2009 2:48 PM
Hide
-2+

great article, should be more like it,
and a few more gaming benches wouldnt hurt either guys!
speaking of headshots yes unreal tournament is probably the most important game to exemplify the value of overclocking and added framerates due to "headshots" and shtuff.

keep up the good work!

jtt283 08/27/2009 2:50 PM
Hide
-8+

stray_gator :
What's the point of using a high-end mobo to overclock a mainstream/value cpu?


Fair question; no one would likely do this IRL, but I think the point here was to see how high the locked CPU could go, so they used a premium mobo.
Paul, now that we know what this specific CPU can do, would it be useful to now put it on a more typical mainstream mobo and see what one might get from the same chip under more typical conditions?
The point would be to answer the following: if my budget just grew by $25, does it make more sense to buy a BE CPU or to get a more premium mobo?

haplo602 08/27/2009 3:37 PM
Hide
-7+

stray_gator :
What's the point of using a high-end mobo to overclock a mainstream/value cpu?



because value mobos vary in stability much more than premium mobos. this article was just about the CPU limit, not the mobo limit.

Anonymous 08/27/2009 3:43 PM
Hide
-0+

Tom's should do a shoot-out between an i7 920 and a 965BE that's had the multiplier taken down to 13x(2.6ghz), then both OCed to the max on the northbridge alone. I'm sure that would close the gap atleast somewhat, but I'm interested to see exactly how much. Maybe they could screw around with the HyperTransport multiplier as well, it might turn out that AMD has been shooting itself in the foot with the unlocked multiplier, when more performance would be had if they were forcing people to use the northbridge.

shadow703793 08/27/2009 4:38 PM
Hide
-3+

Good write up; but PLEASE do NOT recommend OCing via Windows. Most pro's here will tell you that same thing. BIOS > Windows for OCing.

shadow703793 08/27/2009 4:39 PM
Hide
-0+

Also how about putting this under WCing or DIce/LN2? :D

Ryun 08/27/2009 4:49 PM
Hide
-1+

In the performance gains and the cpu tweaking page the graphs for world in conflict are switched.

dirtmountain 08/27/2009 5:28 PM
Hide
-7+

Excellent article! Thank you for the work.

DarkMantle 08/27/2009 5:45 PM
Hide
-0+

Very good article!. Ryun is right, those 2 graphs for World in Conflict are switched.

Upendra09 08/27/2009 6:06 PM
Hide
-0+

I was planning on OCing but this article has made me afraid to OC, it seems there are a lot more factors involved in this than i thought.

saint19 08/27/2009 6:43 PM
Hide
-0+

Really good article, in the pass I has a X2 6400+, and only can overclok 100MHz....now with the 955 I have 600MHz more that the stock frecuency....

cybot_x1024 08/27/2009 7:40 PM
Hide
-0+

nice article.
Amd has really improved overclockability with the dragons.

Anonymous 08/27/2009 8:27 PM
Show
bustapr 08/27/2009 8:36 PM
Hide
-2+

wow great increases fom a triple core. 2.6 to 3.7 is great!

Anonymous 08/27/2009 8:39 PM
Hide
-7+

Shreder: You are a perfect example of a brainwashed sheep. Core i7 has been shown to have a definite advantage in:

Video Rendering(I don't care, maybe you do)
Synthetic Benchmarks(yawn)
Specific games that have been "optimized"(rigged) to perform better on an i7

Other than that, the advantage ranges from neglible to non-existant. Unfortunately, there are people like you who swallow every bit of the fanboy articles with cherry-picked benchmarks...

Boxa786 08/27/2009 9:29 PM
Hide
-0+

Like Shadow said, its obviously a really good cpu, for overcloking from amd,

lets see how high it can go ;D


Sponsored links

Related articles

  • Well, so far I've only talked about Intel CPUs. These CPUs are in the majority, but there are also CPUs from Cyrix, IBM and AMD. What about overclocking these? Because Cyrix, IBM, and AMD have always lagged behind Intel and its Pentium CPUs in terms...

  • We did try to overclock our Radeon 3850 AGP to see if we could squeeze any extra performance out of it. We were quite keen to demonstrate if the AGP 3850 could keep up with its 3870 cousin at identical clock speeds, to further examine if the AGP bus...

  • Last month, we reviewed the Monarch Hornet Pro with an AMD Athlon 64 FX-60 at stock speeds, with specially overclocked graphics cards from EVGA. Interestingly, we can see how the new AMD CPU overclocked plays into game performance when we compare...