Ozren Zagmester - editor at PCEkspert.com - and his team have discovered a pretty unusual behaviour of GeForce FX Ultra cards. There appears to be a serious flaw in the Flow FX cooling control routine - a bug that could damage your brand new hardware. According to his report, this affects at least the Nvidia reference models, Gainward and MSI FX products.
Test system (even though this will probably work on any system): AthlonXP 2400+ Chaintech Zenith 7NJS nForce2 board, NVIDIA nForce 2.03 drivers 2x 256MB Infineon PC3200 Gainward GeForce FX 5800 Ultra, NVIDIA Detonator 43.45 drivers Terratec Aeron Sky 5.1, latest XP drivers, too lazy to look up as it?s unimportant anyway DirectX9, Windows XP Pro SP1 To make a GeForce FX 5800 Ultra card suffer great pain, apart from Detonators 43.45 (we will test other versions of Detonators during the night) you need a 3D screensaver. Even the OpenGL screensavers like Pipes that come with Windows are OK, but for some serious ?firepower? (to make the card extra hot in no time) you need a screensaver like Matrix Reloaded from www.uselesscreations.com or, the one we used the most, DiveVisions 2.0 from www.atlantis3d.com . This behavior was first noticed by Denis Arunovic from our team, and after he called me in the middle of the night, I joined the ?hunt?. Set up the screensaver to turn on itself after 1 minute, so you don?t have to wait too long. After the screensaver starts, you?ll hear the fan on the GF FX 5800 Ultra start spinning. Just wait around 5-10 secs and you?ll hear the fan stop! The 3D screensaver will continue playing on the screen, and after some time (depending on the screensaver) you?ll start seeing artifacts, or in the case of DiveVisions, the screen will look like the monitor was having some interference from a strong magnetic source. You can leave the screensaver running as long as you feel its safe, but don?t overdo it. We tried this around 10 times and were cautious enough not to let it run to long, as the temperature on the card, according to the drivers, reached 95-100C. According to my finger, the drivers were not lying (ouch!). When you end the screensaver, you?ll realize that your 2D screen is messed up and wavy. At this point the fan still won?t be running. To make it run, start something like 3dMark 2001. After you start the demo/benchmark, you?ll finally hear the fan! It will seem as if the 3dMark crashed, but just let it unattended. You?ll see some bizarre things but after a while the card will resume working as normal - when the fan cools it down (the cooling, when it works, is excellent, at least on the Gainward card). This behavior was confirmed by Croteam who tried it with a NVIDIA reference board they received from NVIDIA Developer Relations, and also by a friend of mine with a MSI GF FX 5800 Ultra card. Also, if you try running the screensaver in the preview mode, the fan will spin the whole time. For this to work, it has to be done with a ?real? screensaver, not with the preview of one. I am off to try this on a different system (just to make sure for one more time) and then I?ll start trying different Detonators. Why this is happening? Well, we think that for some reason when using a 3D screensaver the card, or its drivers, decide the card is not running in 3D mode and stop the fan. The problem, of course, is that regardless of the temperature the card reaches, the fan won?t start running again (as long as you don?t exit the screensaver and start running 3dMark or some game like Il2 Sturmovik, Quake 3, etc.). This means that NVIDIA has made a big overlook on how the whole system of cooling-on-demand (i.e. when you are in 3D, or when you a reach high temperature) works. Basically the whole thing obviously works on the basis that the card/drivers will realize they are running in 3D, instead of also taking the temperature in consideration. I mean, you have the bloody thing that measures the temperature, why not use it as you should? Update: Well, this is bad! The thing is still running, with the temperature of the GF FX 5800 Ultra heatsink currently at 95.2C (and rising) and of course, the fan isn't working. All this is with a system that is not in a case, but out open at the table! I just installed 43.45, left everything at default, and the same thing happens! New config: P4 2.4GHz (533FSB) Gigabyte 8GE667 Pro i845GE mobo 1x 256MB Corsair XMS3500C2 CL Audigy (Driver update 31.12.2002) GF FX 5800 Ultra of course Rest is the same, DX9, Det 43.45s, ...
