I've got a freshly built machine from new parts. I've followed all the manuals and installed all the parts into my case.

It works - to an extent. I see the appropriate info on my monitor when booting and I can enter the BIOS setup and browse the options (and presumably change them).

But I have a problem. Whenever I start up the machine, after a while my video output stops (monitor indicates no video input), and my CPU fan starts spinning much, much faster.

It doesn't matter what I'm doing, I could be browsing the BIOS setup, have booted to a DOS prompt or be booting from the Vista install disc - after a while this happens.

My (relevant) system parts are:
Asus Maximus Formula motherboard
Intel Q6600 processor
Coolink Silentator CPU fan (instead of the fan that came with the processor)
ATi Radeon HD3870X2 1024MB video card
OCZ Reaper HPC 4096MB PC2-6400 memory
Cooler Master Real Power M850 power supply

Thanks in advance for any help.

I had the same problem recently with outdated drivers on the motherboard cd. I uninstalled the old driver, and downloaded and burned the newer version off the motherboard manufacturer's website. That did the trick. If that doesn't work, check your bios version at the post. It should be listed at the top or bottom of the screen. I never recommend flashing the bios unless absolutely necessary. If you already have the latest version, then you're good to go.

I have the 0907 version of the BIOS pre-installed on my motherboard. That's the newest non-beta version.

Unfortunately, that means I can't fix my problem by upgrading the BIOS.

Update the mobo bios
Update mobo drivers
Get the latest driver for the 3870x2. From ATI not from video card vendor.
Are you using vista 32 or 64. Make sure your drivers are for the appropriate vista version.

When the computer is running place a meter on the video card power supply. Check if you are getting the right amount of voltage.

Its always a good practice to place the video card on a separate line/rail. Don't share it with any load such has HD or optical drives. Take note your video card will draw significant amount of power (3870x2).


Set your bios settings to default.... What i mean is no overclocking

BIOS 1004 is latest BIOS. That version is only BETA to the 45nm Quads that just came out, that's why it's labeled as BETA. 907 is labeled BETA also, Wolfdale. I used 907 for a long while. Have been using 1004 for weeks now. Go to BIOS and 'default' the BIOS and save and exit. See if that helps. Then in BIOS set the RAM voltages and timings to Mfg. specs. PC6400 is 2.0-2.1v and try 5-5-5-15 for starters.

See if the out-of-box bios is the earliest version, if not, downgrade to the earliest version bios. Asus (along with Abit) rush released a chain of bad, unstable bios for Yorkfield support. If you use Q6600, you don't need the new bios. The early version is full featured, and fully stable.

I figured it out, there were two seperate slots on the video card for power, and I had connected only one.

I feel rather stupid because of it, but in my defense the video card manual was 100% related to software, there was nothing about hardware installation.