TIM Review V2 – AMD Installment
Sunday, 13 June 2010 18:44
Thermal Testing Methodology/Specification
My TIM tests are a derivative of my waterblock tests. I use Dallas One Wire DS18B20 temperature probes at various points through my watercooling loop and at the air intake to measure temperatures, I use the same pump and block on every test, and use good testing practice by performing 5 mounts with pre-measured TIMs and 7 mounts with every other TIM. Where applicable, I follow manufacturer’s installation procedures to the letter. For my TIM tests, I’ll be plotting temperature vs. time, in the form of a 120 minute moving average (or less for the first two hours of data). A moving average is used to smooth out the noise associated with this kind of measurement and to maintain a very high precision of information. A typical TIM test, in raw .CSV outputs, will include roughly 6,500,000 data points per TIM. In the end, all that data can be processed down to one value: what temperature the TIM provides.
I will be examining two specific components of TIM performance: how long it takes to cure (if within the 12 hour testing time) and, more importantly, what kind of temperatures an end-user can expect.
A single 12hr test per mount with 5-7 mounts was completed for each TIM, depending on application method. Everything was held consistent between tests and everything was logged.
- The processor I’m using for this test is an AMD 1055T Thuban. I’m running it at 3850MHz at 1.62V loaded on a Gigabyte XTA-UD4. It is unlapped. I’m running 2GB of G.Skill DDR3 1333MHz. The VRMs, northbridge, and southbridge are watercooled by an EK GA-AMD kit on the radiator subloop of my testbed. The video card is a passively cooled ATi 4350 running in the lowest PCIe 16x slot. The board is sitting on my desk and airflow is provided over the RAM.
- The watercooling loop I’m using is very untraditional, but allows me to test the way I want to test.
- It consists of a two MCR320s with three pairs of Yate Loon D12SH-12 fans in push/pull on each radiator. I use a Koolance PMP-300 pump on the radiator subloop as well as the EK motherboard blocks with Koolance QDCs.
- For the block subloop, I use a Koolance CPU-360 for its consistent mounting and a Laing D5 at setting 5. Also in the loop are three Laing DDC3.2s (turned off) as well as three Koolance KM-17 flowmeters to monitor and ensure there is no change in flowrate during a test or between tests.
- I use a shared Koolance reservoir between the two subloops.
- I do a five/seven mount test, each with their own TIM application and full cleaning between. On the five-mount TIMs I discard the worst mount and average the remaining four. On the seven-mount TIMs I discard the two worst performing mounts and average the remaining five. I also present the best mount results as their own comparison as I feel it is indicative of what you can expect on a near-perfect mount. As a reviewer, I feel it is my duty to present the reader with performance numbers of a product that represent what its typical performance is and I also present the average performance data.
- I have 25 temperature probes in use: 24 Dallas DS18B20 Digital one-wire sensors and 1 AMD thermal sensor in the processor.
- For temperature logging, I use OCCT v3.1.0’s internal CPU polling that is performed every second and is automatically output to .CSV files. I also use OCCT for loading the CPU. For air intake and various water temperatures temperatures, I use Crystalfontz 633 WinTest b1.9 to log the Dallas temp probe data on my Crystalfontz 633. I also use WinTest b1.9 to log flowrates. I have found, much to my chagrin, that programs like RealTemp, CoreTemp, Everest, etc., all have their own massive flaw in temperature logging that prevent them from being used for such a test. These flaws range from data formatting issues, to sensor polling issues, to random, yet common, stalls in the software (especially when logging).
- For processor loading, I find OCCT v3.1.0 to be extremely competent. With the Small Data Set setting, it provides a constant 100% load (so long as WinTest b1.9’s packet debugger is fully disabled) and is extraordinarily consistent. It allows me to, in one button push, start both the loading and the logging simultaneously, which helps. I immediately also start to log the Crystalfontz data via WinTest b1.9. I run a 12 hour and 5 minute program, the first minute is idle, then I have 12 hours of load, and then 4 minutes of idle.
- AMD thermal sensors are not particularly realistic in their readouts. I often get idle readouts below ambient and load readouts within a few degrees of water temperature. In addition to the unrealistically low readouts, their response curve (CPU vs. water temperature with cooling and load held constant) is non-linear. I mapped the entire range of applicable temperature readouts and have remapped the outputs in my Excel spreadsheets so that every one degree increase in water temperature results in a one degree increase in CPU temperature readouts. This must be done to ensure that any variation of ambient and water temperature do not have any effect on the outcome of the data from testing.
Installation Notes and Procedures
Being an entirely different form factor of TIM, it’s not surprising that Indigo Xtreme has a new installation method. Included with every kit is a six page information and instruction guide, within which there are roughly four pages of instructions that you must follow carefully. Every step is there for a reason and it’s crucial that you install it as prescribed. While four pages sounds bad, installation of Indigo Xtreme is actually pretty easy. The first time you do it, it feels a little foreign, but once you do it once, it feels like second nature after that and you’ll be able to do it quickly. In the grand scheme of things, the only difficult thing about it is that it is different.
Here is my summary of mounting Indigo Xtreme:
- If switching from another TIM and using watercooling, save your overclock settings (either on a piece of paper or to CMOS) and set your CPU to stock speeds and voltages. If on aircooling, set stock speeds and overvolt slightly.
- Shutdown, tear down, and orient the PC so that the motherboard is horizontal to the ground. Not sorta horizontal–actually horizontal.
- Clean the CPU and base of the cooler with the included supplies (wear the gloves!). The clean room cloth and solvent wipe are great! You’ll probably be looking online to find where you can buy the solvent wipe because of how effective it is (though it is a bit smelly).
- Install the CPU and open the little case the Indigo Xtreme comes in…peel off the plastic layer labeled “bottom.” Place it on the CPU as directed.
- With your finger and using moderate pressure, tap downward over the entire IHS of the CPU. This step is more important than it initially sounds.
- Peel off the plastic labeled “top” and remove your gloves and install your cooler with even pressure (like normal). You can leave the gloves on if you want, but thumbscrews are really tough to use while wearing them.
- Start up your computer and boot into windows. Open SpeedFan and start charting your core temperatures. Your temperatures will be really bad, that’s normal.
- Start a constant loading program, OCCT, Prime, etc. (Linpack variants might not be that great for this due to the lack of a constant load). Unplug the pump or your fan (pump for watercooled setups, fan for aircooled setups). Yes, it’s okay. As a test, I ran mine under load for approximately five minutes without a pump on; it sounds scary but it works fine.
- Watching SpeedFan, your core temperatures will max out almost instantly. Again, it’s totally fine. If you’re watercooling, your temperatures will drop from 99-100 to the 80s after roughly 10 seconds, let it run for a bit more and then you can plug your pump back in and then let it run for about a minute to cool down before shutting down. I left my pump unplugged for a minute each time, it worked great for me. For an aircooled setup, this process will take a little longer–roughly 5-10 minutes. Just be patient, it’s worth it.
- You can turn your computer vertical again, or however you want to run it. You can start your computer at your overclocked settings and run to your heart’s desire. You’re all done installing Indigo Xtreme!
AS5, MX-2, IceFusion, and Shin-Etsu
Considering these are all classic pastes, installation of these should be more familiar and therefore a little easier. I’m a fan of a bead in the center, varying its size depending on the consistency of the paste. Unlike with Intel CPUs, Arctic Silver recommends using a bead on lidded AMD processors. IceFusion does come in a tub, but I have put it into a large syringe in hopes of maintaining a consistent consistency–it seperates very easily when it’s in the tub and the oil layer performs drastically differently than the white-goop layer.