Replacement cooler for X800 XL?

I've got a HIS X800XL, and it's now on its second Arctic Silencer, the first one the fan just got so slow the card started to overheat & while this card was repaired (or replaced), the cooler is starting to get very noisy when the the system boots up. It's getting very dusty around here, so I'm wondering if dust is clogging up the fans, though having said that why are the chassis, PSU & CPU fans all working perfectly? Anyway if I'm eating Arctic Silencers what would people recommend? I'm thinkin' replace the cooling solution, in this respect it can be water or air a long as it fits in a Silverstone SG01 & if it's water will be able to take a CPU as well.

My first idea is a Zalman reserator, however I'm not totally convinced of it being able it to cool effectively with the 78mm headroom I've got above the CPU (ie sharply turned/kinked tubes.

Im worried now i just got a silencer for mine. What should I be looking out for as the fault develops?

First one the fan just got slower and slower, this current one is just loud (almost like a very quiet hammer drill type sound). Personally I'm thinkin' it's something to do with dust, there's a building site near here and we're forever cleaning brick dust off everything (that's a very fine clay dust that'll absorb anything such as any lubrication oil in a fan :(, it also kills off vacume cleaners)

btw. I will add that I have an Arctic Cooling 3 for Rad 9600 XT and that has worked flawlessly for all the time that I was using it, which was before building started.

Perhaps try the Zalman VF700-Cu?

How do these compare? Also how does the chassis temp change? As it doesn't exaust the warm air out the chassis

i currently have the NV5, if all things go as planned my VF700CU should arrive tomorrow, i could let you know the differences in internal chassis temps. there isnt much info regarding this, im very curious myself but from what i see, the VF700 is definately better at cooling the GPU.

I had an artic cooling vga cooler for my 9800pro, imo back then it was of high quality but lately the newer ones (had one for my 6800gt, and after a while it just packed up! :()

I have a powercolour x800xl pcie and bought a Zalman VF700-Cu which i'm really glad i bought!! The build quality is amazing, you also get ramsinks. Is is inaudible on either high or low. I'm currently running it at low at the moment and with using ati tool to overclock and check out the temps. it is....
Idle Core 36c
Load Core 52c

That is when it is overclocked from 400/490 to 434/545

(doh sorry didn't monitor my temp change in the chassis!)

But i recommend the vf700cu!! :D

Idle
- CPU 31C
- GPU 31C
Load
- CPU 59C
- GPU 64C
Chassis temp is somewhere between 27 and 34C (it's almost entierly related to PWM/OTES fan speed)

FYI Games rig -
Cheiftec TX-01 style chassis - old layout
Athlon64 3800+
Abit AN8 (anyone know where the chassis temp sensor on the AN8 lives?)
2GB PC3200
Rapt 74GB
Samsung? 200 GB
X800 XL
NeoPower 480w