Another real-world case study:
I had a Pentium 4 3.0E Prescott PC watercooled by the Koolance EXOS. It was stable, but the noisy fans when the Koolance went into accelerated mode (temps >= 45C) were driving me mad. The UK is having an unusual heatwave right now, so room temperature is nudging 30C even at night with the windows open (this explains why I can't sleep and instead find myself typing this message). Noise is subjective and I am more sensitive than most. My PC has been carefully crafted out of quiet components like a 500W SilentMaxx fanless PSU, Maxtor hard drives with FDB motors and undervolted Pabst case intake and exhaust fans. I then added a GeForce 6800 Ultra AGP card. A Prescott and a GF6800U, can you think of a more heat-generating combination of PC hardware? At this point, the Koolance was pretty much running in accelerated mode all the time. Also at this point, my PC started crashing randomly and it was due to overheating because leaving the case sides open always fixed the problem. So I traded my CPU in for a Pentium 4 3.0C Northwood and took this opportunity to order a Zalman Reserator 1. I used two litres of de-ionized water and a cupful of Koolance anti-corrosion/anti-algae agent to fill her up. I used the Zalman GPU block (large type) with Koolance GPU screws to cool my 6800U. The screws Zalman provides are too fat to fit through the holes on the GF card, which is why it wasn't compatible. Using the slimmer screws from the Koolance kit fixed the problem. Other than that, the Zalman GPU block is a great fit, so I don't know why Zalman doesn't add two slimmer screws into their kit to make it compatible with the 6800 cards. Unfortunately, I couldn't re-use my existing Koolance GPU waterblock (which is beefy: rated at 180W) because the pipe sizes were not identical (Exos uses 1/4 inch tubes, Zalman uses 3/8 inch tubes).
So now, current PC has:
- P4C 3.0 GHz
- Intel D875PBZ motherboard
- inno3D GeForce 6800 Ultra
- 5 hard drives (4 in RAID-5 config on an Adaptec 2410SA controller)
- Reserator 1 cooling CPU and GPU using stock Zalman Reserator 1 waterblocks
Idle temps (after 10 hours of idling at the WinXP desktop):
Case ambient: 38
Temps under load (after 12 hours of looping two copies of Prime 95 and 3DMark03):
Case ambient: 44
I used the integrated temp sensors in my CPU, GPU, motherboard (for ambient) and HDD to read these temps. I understand they may not be entirely accurate, but I don't care about exact temperature values to the nearest degree. All I care about is to have a fast, 100% stable and quiet computer which is being adequately cooled.
Note that room temp was sometimes exceeding 30C during these tests, which is very unusual for England!!! That's as hot as it gets in England, so I expect the Reserator to perform even better when the English climate returns back to its normal, colder temperatures.
Overall, I could not be more impressed and pleased with the Zalman product. It's absolutely quiet and works startlingly well. I can now run my PC with the sides closed and there are no crashes. 100% stable. Best of all, the only way I can tell my PC is on is by looking at the screen to see if it's showing anything. That's the way it should be. I love quiet computers, which is one of the reasons why I love Macs. My Powerbook Al, on which I'm typing this, is absolutely silent. No fan noise whatsoever. Bliss...
If anyone would like to buy a second-hand EXOS Al in the UK, feel free to email me or watch eBay.co.uk.