After the initial installation, I removed the heatsink to inspect the contact area. I was impressed to see that the thermal compound was almost completely squeezed away. The ATI logo on the core is very clearly visible. This is the best contact of all GPU coolers tested so far and probably contributes a good amount to the cooler's performance.
For the overclocking tests I used my ATITool overclocking utility version 0.24 Beta 5. ATITool has the unique ability to detect artifacts, or flaws, in a rendered image. As defined by ATITool, the maximum stable overclock on a card is the speed at which it is able to consistently (15 minutes in this test) produce no errors, or artifacts. ATITool detects ANY artifacts, even ones which will not be visible in game. Using the human eye to detect artifacts introduces subjectivity into the test, so despite the fact that an ATITool tested overclock will be characteristically lower than a human one, I will use this.
Thermal testing was done on a Radeon X800 XT. Temperature data was obtained by reading from the internal thermal diode of the R420 GPU chip. Idle temperature was measured after letting Windows sit one hour at the desktop. Load temperature was measured after running ATITool scanning for 30 minutes. Both at the card's default clocks of 500 Mhz core and 500 Mhz memory.
Arctic Silver Lumière was used as thermal interface material for the GPU core in all installations. Lumière is a specially engineered testing compound - it needs no settle in time to reach its maximum performance, but it's not designed for permanent use.
A 7V setting is possible by connecting the fan connector's black wire to the PSU's 5V output, and the fan connector's red wire to the PSU's 12V output (12V - 5V = 7 V).
The dynamic fan setting of the card changes fan speeds from 33% (idle) up to 100% (load). The stock cooler was also tested with forced 100% fan speed for better comparison.
|Radeon X800 XT||Maximum Core Clock||Sound level||Temperature Load||Temperature Idle|
|Stock cooler - dynamic fan||534 MHz||Quiet(idle)|
|Stock cooler - fan 100%||545 MHz||Noisy||67°C||39°C|
|Zalman VF700-AlCu 5V||546 MHz||Almost inaudible||69°C||39°C|
|Zalman VF700-Cu 5V||549 MHz||Almost inaudible||64°C||37°C|
|Zalman VF700-AlCu 7V||546 MHz||Quiet||66°C||38°C|
|Zalman VF700-Cu 7V||549 MHz||Quiet||64°C||37°C|
|Zalman VF700-AlCu 12V||549 MHz||Acceptable-Quiet||61°C||36°C|
|Zalman VF700-Cu 12V||551 MHz||Acceptable-Quiet||60°C||36°C|
|Watercooling (Water ~30°C)||564 MHz||Inaudible||42°C||33°C|
Running the VF700-Cu completely passive is not possible.
The is no difference in maximum overclocking when running at either 5V or 7V.
At 12V the fan is moving a good amount of air while still not being noisy. This is because of the sound quality, it sounds more like a swoosh than like the typical fan whine.
Overall there is not much overclocking difference between the different input voltages. If you have a little bit of airflow in your case it should be perfectly fine to run at 5V for day-to-day usage with some overclocking.
Nothing can beat watercooling on the X800. It seems the core just loves low temperatures. It is still impressive how close to watercooling you can get with an air cooler in the $40 range.
The biggest disadvantage is that the fan is not connected to the video card's fan power connector. This means that on cards which support dynamic fan controls, like all X800s, you will not be able to use that feature and your fan will constantly run at the same speed. Also the extra cable with the bulky connector is a bit disturbing for people who like to show off their case insides.
Value and Conclusion
- The VF700-Cu is selling for about $40 ($5 more than the AlCu). If you have the choice, go with the Cu and run it at 5V.
- Great compatibility
- Good performance
- Very easy to install
- Ramsinks included
- Spare parts included
- No 7V option for fan
- Fan does not connect to video card fan power output
- Minor installation issue
The performance difference between the VF700-Cu and the VF700-AlCu is not stellar, but it is there. Performance is good without being noisy. There were no compatibility issues. If you are looking at getting either the VF700-Cu or the VF700-AlCu go for the full copper version, the improved performance is worth it.