I've got an all aluminum Lian-Li case. All aluminum = better thermal dissipation than steel, lighter than steel, easier to cut/mod than steel and more expensive than steel. It's worth it.
The processor is a Pentium D 805 - one of the hottest running dual core 64 bit Pentiums around but it's also a nice overclocker's chip.
The motherboard is an Asus P5b Deluxe with heatpipes instead of fans to cool it's components. Is it crazy logic to think that several noisy fans inside cool less efficiently than heatpipes because the small fans disrupt good airflow and blow warm air onto components? I don't think so.
The case has 1 120mm front intake, 1 80mm rear intake and one 80mm exhaust fan at the top of the case - blowhole style. The PSU also has 2 fans to exhaust... now think about that rear 80mm intake. It's right below the PSU exhaust. What are the chances it will suck in warm air from the PSU exhaust? Very small if you have the PSU fan duct from Lian-Li that directs the PSU exhaust to the left. I would rather have this exhaust direct the hot air up due to where the case is sitting in my workspace and I may look into making that a reality in the future. The case sits at my right as I type this and the hot air gets blown in my general direction.
The CPU cooler is an Apack Zerotherm CF800. It cools about as good as the stock Intel solution but my OEM processor doesn't come with the Intel cooler. The CF800 cost me about $30 at Newegg.
For reference, 35c = 95f, 40c = 104f, 45c = 113f, 50c = 122f, 55c = 131f, 60c = 140f, 65 = 149, 70 = 158, 75 = 167, and 80c = 176f.
Before I even think about attempting to overclock I'm going to make sure my cooling is good. The results of my first test were scary as hell! To test I'm running 2 instances of Prime95 to push both cores to 100%.
1:09 - Start Prime95 x 2
1:11 - proc core temp = 70c
1:13 - proc core temp = 71c
1:15 - pct = 72c... that's 159f BTW
1:24 - pct = 73c, motherboard temp = 51
1:36 - stop Prime95 x 2
1:37 - pct = 57c mbt = 51c
Went into the BIOS, turned off Asus' Q-fan control of the CPU fan then started test 2.
1:43 - start - pct = 65 mbt = 50c
1:44 - 70/50
1:45 - 71/50
1:46 - 73/50
2:02 - 73/53 - stopped test.
BIOS, disable all Q-fan control so all case fans running full throttle, start test 3.
2:08 - start - 62/51
2:09 - 66/51
2:10 - 69/50
2:11 - 70/50
2:16 - 72/51 - stopped test.
Something's either really wrong or I'm confused about what to expect. Did some thinking, took side panel off and just looked around. The exhaust out of the PSU was 140f and the top panel was arund 120f this whole time - I used a meat thermometer to measure exhaust temps. I felt the area of the back panel just below the PSU exhaust and it was very warm. Felt the back panel near the bottom and it was cool... this confirms a thought I've been having off and on about putting a 120mm fan intake in the bottom of the case! Still, I must be missing something so I put the side back on and power up into the BIOS. At some point, at a loss, I grabbed a tissue and held it up to the rear intake to see just how much air it was moving... it was then that I had a small rush of joy quickly overtaken by frustration. That rear fan that should have been an intake was exhausting air! Wow... it was something obvious! I didn't mount/install this fan but that's just an excuse... and changing it requires a bit of work due to the duct attached to the inside of the fan to direct the INCOMING air onto the processor. I felt so damned stupid.
8:00 - took a long break, a nap and then put the case back together to start the tests again.
8:10 - cold boot cpt = 49c mbt = 35c
8:11 - 45/37 - little to no load - CPU fan speed = 1298... first time I've seen it under 2200 RPM ever!
8:14 - 45/38 - little to no load - CPU fan = 1298
8:15 - start test - 59/39 - CPU fan = 1360
8:16 - 61/41 - 2057
8:19 - 63/45 - 2109
8:20 - 63/46 - 2163
8:25 - 64/50 - 2220
MUCH BETTER! I'm no longer seeing a core temp increase of 10 degrees + from normal/average operating temperature.
Now things are performing more in line with what my original expectations were of this Pentium D 805... now I can consider overclocking a small bit. I still haven't stopped that last test.
9:30 - 65c/53c - 2343 RPM
The PSU exhaust still sucks... errr blows. Gotta do something about that before summertime for sure. It's a cheap old 300 watt PSU I had lying around - I'm not in love with it much even before this experience... but at least it hasn't failed yet under these temps.
BTW... Friday morning I got another email from Newegg. It had the UPS tracking numbers for my shipment... that I had recieved on Wednesday. Never. Paying. 2.99. Again.
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