Temperature and Overclocking Testing
Cooler Testing Methods
To best gage the quality of the GPU cooler under review, GPU temperature was taken with the graphics card idle and under load. To replicate GPU idle conditions, the system was rebooted and allowed to sit idle for 30 minutes. To replicate a stress graphics load, FurMark was run over a 30 minute period running at 1280×1024 resolution and 4x MSAA in Burn-in Test mode. After each run, the system was shut down and allowed to rest for 10 minutes to cool down. This procedure was repeated a total of six times for each cooler – 3 times for the stock speed runs, and 3 times for the overclocked speed runs.
Temperature measurements were taken directly from the GPU thermistors using TechPowerUp GPU-Z v0.7.2. For both the idle and load temperatures, the highest recorded value in the application were used for the run. Note that the temperature values are reported as deltas rather than absolute temperatures with the delta value reported calculated as GPU temperature – ambient temperature.
Stock Temperature Testing
The graphics card temperature testing was conducted at stock speeds for the EVGA GTX 670 FTW card in two configurations – with the stock EVGA cooler and with the XSPC Razor GTX680 water block installed.
Just at stock speeds, the temperature difference is dramatic between the stock EVGA cooler and the XSPC Razor GTX680 water block. At idle speeds, the observed differences a full 8C drop in temperature with the card idling a mere 2C above ambient with the water block installed. The difference was found to be even greater under load with the card temperature measured at only 21C over ambient. Compared to the 55C over ambient temps measured using the stock cooler, that is quite a difference.
Overclocked Temperature Testing
Using the EVGA PrecisionX v4.20 overclocking software, the graphics card was overclocked to its highest stable settings with the XSPC Razor GTX680 water bock installed on the card. For details on the overclocked settings used, please see the overclocking section below.
Even with the added voltage and speed of the GPU and memory, the graphics card temperatures did not exceed 26C over ambient under load and 3C over ambient at idle. The measured load temperatures illustrate just how well the block is able to cool the card with the overclocked temperatures exceeding the stock speed temperatures by a 5C delta over ambient. XSPC definitely did their homework with the design of the Razor GTX680 water block.
Manual Overclocking
While the a water block does not in any way directly influence the overclockability of the graphics card, it is an effect heat dissipater. This results in lower component heat, leading to better overclocking potential of the graphics card. This indirect relationship between card cooling and overclocking seemed to be the case with the XSPC Razor GTX680 water block. Overclock testing was performed in conjunction with the XSPC water block to demonstrate the card's increased performance potential.
With the help of EVGA's PrecisionX software (v4.20), we were able to get the GTX 670 FTW card running with a +100MHz GPU speed and a +650MHz memory speed. The actual running speeds after boost clock adjustments came out to 1228MHz GPU speed and 1879Mhz memory speed under load. For this overclock, the Power Target value was set to 145% with the GPU voltage set to 1.175V. We were able to get the card running at a +165MHz setting on the GPU and +750MHz on the memory, but it would not stabilize. Graphics card stability was tested by performing a full run through the Unigine Heaven benchmark at max settings and 1920×1080 resolution without crash or artifacting. Once the Heaven benchmark run stabilized, the card was torture testing over an eight hour period with FurMark running at 1280×1024 resolution and 4x MSAA in Burn-in Test mode.
EVGA PrecisionX profile settings
- GPU CLK OFFSET – +100MHz
- MEM CLK OFFSET – +650MHz
- POWER TARGET – 145%
- GPU VOLTAGE – 1.175V
Performance numbers
- GPU Boost / K-Boost Clock Speed – 1228MHz
- Memory Speed – 1879MHz
- GPU voltage – 1.175V
Is there a reason we you only
Is there a reason we you only show the temp over ambient vs actual temp? Most households would have ambient temps between 22-26. I just think actual temp would have been easier for an idiot like me to comprehend.
Of course, there is ambient
Of course, there is ambient temp within the case, which is probably what should be used… but still confusing. Just give me temps! TEMPS!!!
We report delta temps instead
We report delta temps instead of actual temps to allow you to calculate what your temps would be based on your house or office ambient. The delta temps are the card gpu temps minus ambient temperature measured at the time of testing. We moved to reporting delta temps rather than measured temps based on user feedback from previous cooler reviews.
For example, typically my home office temp ambient is between 26-27C. For stock temps with the ambient at 26C, the GPU temp should idle at 28C and go up to 47C under load temps. If the ambient were 21C, the idle temp should be 23C and load at 42C.
add the numbers in the graphs
add the numbers in the graphs to your ambient. There’s your temp.
your ambient: 22
card delta: 10
22 + 10 = 32 degrees
math = gud
Yea, I just didn’t realize
Yea, I just didn’t realize what I was looking at initially. Many times I elect to just jump straight to the graphs, and they didn’t state anywhere that they were based on ambient… had to actually read. Knowledge is power!
Finding it hard to justify
Finding it hard to justify $99 for this waterblock.
The 10% overclock is not unrealistic for an air cooler, especially an aftermarket cooler.
Aftermarket coolers are typically very quiet.
Real-world usage will not push a 6xx/7xx series card with an aftermarket cooler beyond 70C, perfectly acceptable ultimate/maximum-use temperature.
Waterblocks are typically made for reference model designs, which fail to match the benefits of aftermarket designs.
If you can find an aftermarket model for the same/near the same price as a reference model, why bother with watercooling?
Keep in mind that the EVGA
Keep in mind that the EVGA GTX 670 FTW card used for the review came overclocked from the factory, so a 10% overclock with that card equates to a more than 20% overclock on a vanilla GTX 670. On a non-factory o/c'd card, the boost clock speed for the GPU typically hits 980MHz.
The choice between using an aftermarket cooler vs a water cooler is a long running debate that really has no right answer. I've been water cooling my rigs for a long time, and prefer that to pure air cooling mainly because of the fan noise associated with air coolers if you want to push the performance limits. It really comes down to the preference of the inidividual enthusiast…
Steel touching copper with a
Steel touching copper with a fluid running between them. I’ve had some issues with this before.
As long as your coolant has
As long as your coolant has some type of corrosion inhibiter in it (which most good coolant's should have), you should not run into any cross-metal type problems like galvanic corrosion…
The coolant is supposed to be
The coolant is supposed to be “non conductive”, so electrolytic/galvanic corrosion is a non-issue. Especially since the steel used is stainless and the copper is very pure and the lifespan of the cooler is much much shorter than it would take for the electrolysis to damage it so badly as to cause a malfunction. Would it be Aluminium instead of steel, it would “pee” in a few weeks.
Most of the good pumps used have a stainless steel part touching the coolant and there are no horror stories floating around.
Mild steel is a completely different story, that much is true.
Morry – i love your reviews,
Morry – i love your reviews, just one question: do things work when you put them back together? jk. keep up the awesome work!
Thanks. And yes, in most
Thanks. And yes, in most cases they do work after putting them back together. There was one time in the recent past were teh take apart result in disaster – but we won't discuss the H80i dissasembly here…
I like to see both because
I like to see both because what many heatsink reviews fail to show is the cooling performance curve with ambient temperature, eg CPU temperature will not scale linearly with ambient temperature, it tapers off slightly as ambient gets higher.
so temperature over ambient may not be the best indicator if you have some test done in a hot environment, where a 5 degree rise in ambient may only cause a 3-4 degree increase in CPU or GPU temperature.
I notice this with my current air cooler.
Good point. I will continue
Good point. I will continue to report in deltas in future cooling reviews but will include ambient temperature at the time of testing as an additional data point either in the graphs or test description.
Typically, my office ambient runs between 25-27C which is most likely typical or a bit hotter than most homes / home offices.
Thanks for the feedback…