To me there looks like there is a serious design/manufacturing flaw with the cooler.

Please correct me if I am wrong, but isn't the main point of heatpipes, is that the liquid inside gets boiled via the hot component and then evaporates up the pipe towards fins which then cool the liquid, the liquid then runs back down and gets boiled Ad infinitum.

How can the liquid get boiled if the pipes are crushed flat 2+ inches from the GPU core.? The picture I am referring to is at the bottom of page 2.

If this is compared to the following product linked below, it is clear from any of the pictures that the heatpipes are not crushed (yes I do realise that there is an extra heatpipe and far more fins and that was tested on the old GPU test rig), but the cooling performance is significantly better for a product that outputs a similar amount of heat.

http://www.silentpcreview.com/article1249-page2.html


Andy

So not great then. It does also seem perilously close in price to the much more powerful GTX650, there are some very creatively cooled versions of that like this MSI:
http://www.guru3d.com/articles_pages/ge ... iew,1.html

I haven't thus far seen a passive GTX650 but I see no reason why it would not be possible by adding an Accelero S1 Plus. At UK prices this would come out as only £30 more than the GT640 for much more card.

RAM sells video cards. That's why the low end cards feature a lot of RAM, then as you step up to real gaming cards such as the 7770 you drop back down to 1GB. I can't tell you how many times a friend tells me about how he got a full 2GB of RAM on his video card for me to find out it is something like an Nvidia 520 that is actually slower than his HD4000 igp.

Very true and even so on the same cards when a manufacturer offers a model with more RAM than the normal models. I fell into this trap many years ago by paying £10 more to have a Geforce FX5600 256Mb as opposed to the 128Mb version. What I didn't realise when I bought it (oh the lack of information we had in those days compared to now!) was that the RAM was clocked slower. I did end up BIOS flashing it back up to the full 550MHz but it never had much headroom beyond that, not to mention the complications it brought for RAM heatsinks over the years. I still have that card with an Accelero S2 strapped to it...

Thanks for the review. I wonder if it's a poor heatsink design or low airflow, or both? The answer in the past has been to strap a low rpm fan to it and see what happens. It'd be a nice followup

That said, the 640 is an abortion of a product and it's corrected in the GTX 650 by simply replacing the DDR3 with GDDR5 RAM. Similar power consumption and big bump in fps.

Could someone explain how a card can use more power (9w) for idle than it does for playing high def video (4-6w) ? I didn't quite understand that.

The graph I believe you're referring to is labelled "Power Consumption, Increase over Idle (Watts, AC)" at the bottom.

Thanks, I just misread it, and didn't see the the word "increase" in the graph, nor the word "more" in the article's concluding paragraph. (lol...no wonder it didn't make sense).

Would this card be suitable for somene who wants a little more than integrated graphics, but does not do any gaming?

I work with Adobe CS5 using a Zotac 430 and plan to upgrade to CS6. I am also looking at upgrading my whole rig when Haswell chips come out next year, including a dual monitor set-up. Just not sure whether the onboard intel Haswell GPU would be enough or if I should consider getting something like this Zotac discrete card. I'm really attracted to it's energy efficiency.

The GTX650 is only a little more and a whole load better card basically because of the RAM bandwidth. I would think for advanced graphics work memory bandwidth would be an important factor? Hence the 650 would be better.

CS6 has the Mercury Graphics Engine which uses the GPU to accelerate certain functions using Open-CL and Open-GL. Here's Adobe's FAQ. Haswell is expected to double the GPU processing power of Ivy Bridge...which would put it in in the ballpark of the HD 6570 and GT 640. So, don't buy the GT 640. If you think the IGP is bogging your workflow down, consider getting a more powerful discrete GPU for acceleration.