Thanks Buds for the help and suggestions.

I found the problem and it was the solution.

My Rampage Formula has a Vantec Spectrum fan in slot six which, besides looking good with the blue LED's, blows air up at the video card. When I replaced the two fan cooling solution of the Visiontek 3870X2 with the cooling solution of the Tri-Fan Asus 4870X2, I thought I would not need the extra air cooling from the Vanrec fan anymore. So I turned it down to the minimum rpm. Guess I was wrong. Apparently the Vantec fan also blew air onto the NB from under the video card.

So, I turned the Vantec Spectrum fan to its maximum rpm. Now my NB temps are coming in at 38°C idle and 48°C for load. It is a bit higher then when I had the 3870X2 card in which was 44°C under load, but I guess with the hotter 4870X2 installed, 48°C is acceptable.


Regarding watercooling, a heatsink on the SouthBridge may be a requirement because there doesn't seem to be any room for hoses and fittings on the SouthBridge waterblock if the 4870X2 (single card or CrossFire) is there and keeps its stock air cooling. Is there anyone who has the Rampage Formula SB under water while keeping the stock air cooling on the video cards?



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Asus X48 Rampage Formula / Intel Q9450 2.66 @ 3.2 / 2 x 2GB OCZ Reaper HPC PC2 8500 /
Asus Radeon HD4870X2 Tri-Fan 2GB graphics card / 24" DeLL Ultrasharp 2408WFP monitor /
Western Digital Raptor X Hard Drive / Two Western Digital Caviar RE2 WD5001ABYS 500GB 7200 RPM SATA 3.0Gb/s Hard Drives /
Creative SoundBlaster X-Fi Elite Pro 7.1 / Creative Gigaworks S750 7.1 Speaker System /
Lian Li 343B cube case / PC Power & Cooling Silencer 750 Crossfire Edition /
IOGEAR GCS1782 GCS1782 Dual-Link DVI KVMP switch with 7.1 audio