Now that we finally have this thing put together, it is time to see just how well it works. I'm still a little skeptical about this no fan cooling system, but we'll give it a go and see if it can handle the load.
Our test system will consist of:
Prolink Impact Ti4200-8x Video Card
Xoxide modified Lian-Li PC60 case
EPoX 8K9A2 Motherboard (KT400 Chipset)
Athlon XP 1800+ Processor @ 1870 MHz (Thoroughbred)
512MB Crucial PC2700 DDR Memory
Seagate Barracuda 40GB HDD @ 7200 RPM
Testing will be simple and straightforward. I'll begin by booting up the system and then letting the machine idle for 15 minutes. This will allow the system to stabilize and give me a reading for idle temperature. After this temperature is taken, I'll run the PC through a few runs of the newly released 3DMark03 benchmarking program. I figure that anything that can slow me down to 4-6FPS is surely enough to stress out the video board. The highest temperature recorded during this will be listed as the load result.
Ambient temperature throughout testing is a constant 23.0 degrees Celsius. All temperatures are being taken by means of a thermal probe that has been secured right next to the GPU. The probe won't be moved between cooling methods so that we can have some consistency in our results.
Results - Idle
While I had fully expected the stock cooler to win this contest, I had really expected to see a bit more of a difference in the results. After all, the stock cooler has a fan in place and also some RAM cooling for the front of the card. So far I'm reasonably impressed with this no fan system, but what happens when we let the video card pump out so many pixels that it literally chokes itself?
Results - Load
I ran these tests again to make sure that they were correct and I ended up with the same basic result. The cooling system with no fan has soundly beaten a stock cooler. How can this possibly be?
To answer this, lets take a look at the principal behind a heatpipe cooling system. Though there is no fan in use, the heatpipe by its nature will take as much heat as possible and transfer it along the length of itself. What this means is that when the GPU starts producing heat, it is absorbed (for lack of a better term) into the very conductive copper tube, or the heatpipe. This heat is carried along its length and taken towards the rear of the video card where the pipe terminates. Some of the heat is dissipated instantly by means of the front heatsink while the rear heatsink dissipates some more of the heat.
Another consideration is that anyone with good case airflow (I believe I qualify for this category) has a natural flow of air that goes from the front lower portion of the case to the upper rear area. A lot of this air is flowing between the processor and the video card (along the rear heatsink of this heatpipe cooler), so this will also help in the cooling process.