|ASUS ENGTX460 DirectCU TOP/2DI/1GD5|
|Reviews - Featured Reviews: Video Cards|
|Written by Olin Coles|
|Sunday, 08 August 2010|
Page 18 of 20
ASUS ENGTX460 TOP Overclocking
If there's one particular message this article should impress upon the reader, it would be that the NVIDIA GeForce GTX 460 is an overclocker's dream. The GF104-equipped GTX 460 already comes with an impressive stock clock speed of 675/1350 MHz, with the GDDR5 running at 900 MHz (1800 DDR). Putting this into perspective, these speed fall between the GeForce GTX 470 and GTX 480 (closer to the latter). Now comes the fun: overclocking the GeForce GTX 460 is as easy as its ever been.
Back in the day, software overclocking tools were few and far between. Benchmark Reviews was literally put on the map with my first article: Overclocking the NVIDIA GeForce Video Card. Although slightly dated, that article is still relevant for enthusiasts wanting to permanently flash their overclock onto the video cards BIOS. Unfortunately, most users are not so willing to commit their investment to such risky changes, and feel safer with temporary changes that can be easily undone with a reboot. That's the impetus behind the sudden popularity for software-based GPU overclocking tools.
NVIDIA offers one such tool with their System Tools suite, formerly available as NVIDIA nTune. While the NVIDIA Control Panel interface is very easy to understand an navigate, it's downfall lies in the limited simplicity of the tool. It's also limited, and doesn't offer the overclocking potential that AIC partners offer in their own branded software tools. For example, using the NVIDIA System Tools utility to overclock the ASUS ENGTX460 DirectCU TOP, I was able to set the graphics clock up to 1350MHz (which is way out of realistic range) but the memory clock was limited to 2160. As it turns out, overclocking the GTX 460's GDDR5 from 1800 to well past 2160 MHz was possible. I needed more...
NVIDIA System Tools Overclocking Utility
My mission was simple: locate the highest possible overclock without adding any additional voltage. In the past, software-based overclocking on ASUS video cards has been accomplished through the GamerOSD program. Now these tasks are handled by ASUS SmartDoctor, which is described as "intelligent hardware protection and a powerful overclocking tool". The ASUS SmartDoctor tool allows users to overclock their ASUS video card's GPU and RAM, and at the same time monitor thermal output. ASUS simplifies the on-screen feedback with notes such as "Your VGA Card is OK.", but more advanced users will appreciate the in-depth data that displays along the upper-right corner.
Unlike the NVIDIA System Tools utility that measures memory clock speeds in dual data rate, the ASUS SmartDoctor utility measure memory speeds in quad data rate. This means that the stock speed of 1000MHz GDDR5 appears as 4000MHz in the utility. While the ASUS SmartDoctor utility worked well to overclock Vcore voltage (not changed, but plenty of range available) and GPU clock speed, the ASUS ENGTX460 DirectCU TOP needed more memory adjustment than this tool could offer. I still needed more...
ASUS SmartDoctor Overclocking Utility
After hitting a brick wall with the NVIDIA System Tools utility (nTune) and again with the ASUS SmartDoctor, I turned to MSI's free overclocking utility based on Riva Tuner. Knowing that the ASUS ENGTX460 DirectCU TOP would need a wider range of clock speeds, I began overclocking with MSI Afterburner 1.6.1. Starting with memory, I slowly raised the GDDR5 clock speed... until I reached the speed limit for this tool: 1170 MHz (2340 MHz data rate). While I would have liked to go further, and take the ASUS ENGTX460 DirectCU TOP's 1GB GDDR5 memory as far as it could possibly go, the jump from 900 to 1170 MHz actually equaled very little frame rate improvement. Using only a memory overclock, Aliens vs Predator performance jumped from 24.9 to 26.7 FPS at 1920x1200. Far Cry 2 performance was bumped from 64.9 to 66.4. Now it was time to work some magic on the GF104 GPU.
MSI AfterBurner Overclocking Utility
As a best practice, it's good to find the maximum stable GPU clock speed, and then drop back 10 MHz or more. While the ASUS ENGTX460 DirectCU TOP was stable in many tests up to 850 MHz, there was an occasional graphics defect. In the end, I decided that 850 MHz with full-time stability is a far better proposition than crashing out midway through battle. Adding the 850/1680 MHz GPU overclock onto the 1170 MHz GDDR5 overclock resulted in some very impressive gains!
Far Cry 2 video frame rate performance increased from 57.4 FPS at stock GeForce GTX 460 speeds, to 71.6, equaling a 25% bump in performance for this DirectX-10 video game. That's a nice start, but DirectX-11 is really where the market's at these days... so I turned to the AvP benchmark for another series of test runs.
Aliens vs Predator jumped from 22.2 FPS at stock reference clock (675/1350 MHz) settings to 28.3 FPS at 840/1680 MHz, resulting in nearly 28% performance gain. What does that 28% mean to you? For $230 the ASUS ENGTX460 DirectCU TOP continues to completely dominate the Radeon HD 5850, but also competes with the $400 ATI Radeon HD 5870. ATI should be concerned, especially after the results we received in our SLI tests.
Want to boost graphics card performance without exiting the game? Activate ASUS GamerOSD anytime during gameplay and adjust the GPU clock for instant overclocking. Real-time FPS (frames per second) status is also available to keep track of performance improvements. The ASUS GamerOSD (On-Screen Display) is a tool for combining ASUS SmartDoctor and video capture tools together without leaving the action. What I found especially helpful was the high-resolution DVD-quality video capture feature, which comes FREE with the ASUS ENGTX460 DirectCU TOP/2DI/1GD5 kit. Programmable hot keys assign actions, and recorded video (saved in XviD MPEG-4 format) or screen shots can be taken on command. These are features you would have to pay for using other software, such as FRAPS.
In the next section, I offer my opinion on Fermi's updated architecture...