Let’s take a look at the results:
At first I would like to say a few words about the results obtained with overclocked GeForce 7600 GT. As you know, this graphics card dissipates not too much heat, and the results show that both, Accelero S2 as well as CoolViva Z1 both do very well with it, the latter is even 1o C more efficient. Without additional fans installed both cooling solutions lose about 7-8o C to the well-known Zalman VF900-Cu LED, but the moment you put the fans on them, both our heroes leave no chances to their competitors. Look at the GPU temperature difference under peak workload: Accelero S2 and CoolViva Z1 cool the graphics chip by about 10o C more efficiently than the standard Zalman VF900-Cu LED. Overall, the chip temperature is very low and I wish it had a positive effect on the overclocking results. Running a little bit ahead, I would like to say that even the graphics processor of the GeForce 8600 GT graphics card cooled with Accelero S2 cooling solution didn’t heat up to 41o C. Excellent results!
Even more impressive results were obtained with a relatively warm overclocked Radeon X1950 GT. As you can see from the design of the stock cooling solution, it is no good for this graphics card. However, how surprised we were when it turned out that Accelero S1 in passive mode cooled this graphics chip better than the stock cooler with its fan running at maximum rotation speed! Unfortunately, CoolViva Z1 cannot boast the same impressive efficiency in passive mode, as the graphics chip gets really hot in this case. However, an 80-mm fan on the lower heatsink of this cooler resolved the issue completely and pushes the temperature 40o C down! This is excellent proof that I shouldn’t have had any concerns about the original design of CoolViva Z1: it works perfectly fine. Accelero S1 and CoolViva Z1 in active mode prove more efficient than Zalman VF900-Cu LED by 14.5o C and 10o C respectively. Moreover, with these two coolers I managed to push the frequency of my Radeon X1950 GT to 688MHz without any stability issues. And the temperature hardly rose at all in this case: by about 1-1.5o C.
In addition I would also like to offer the diagram with Radeon X1950 GT PCB temperature:
It is quite logical that in passive mode both new cooling systems cannot catch up with the competitors, because there is no airflow to cool down the PCB components. However, the temperature is not critical at all under both: Accelero S1 as well as CoolViva Z1. Once the fans are installed the situation improves, although I have to admit that the front 120-mm fan of Accelero S1 makes it more efficient than CoolViva Z1.