06-06-2010 01:58 AM - edited 06-06-2010 04:28 AM
Can this actually be done without opening the casis?
I didn't want to open it again, I did it earlier but the connectors and flat ribbons inside could be quickly damaged.
So I just returned the box and drilled inside. Nothing from those drilings should remain in the PC. I took the risk, thinking at opening it again only if something from my drillings dropped inside, which - almost - wasn't the case.
The 4 - 3.2mm - holes making a square at the bottom right of the picture I took should be enough.
Moreover, the fan is just behind those holes. If you drill to far, you will destroy the fan.
I already wrote: don't do that
I'm feeling this makes a change at higher room temp and CPU load. It wont stop the fan or provide passive cooling, but it seems the CPU temp decreases (so the fan can also run slower, or less longer at higher speed if higher CPU temps where reached).
Others may soon confirm if this really changes something or not.
06-07-2010 11:44 AM
Like many of you I registered only to post in this thread.
Yesterday I took the plunge and disassembled my U350. It's not too hard once you figure out how to remove the keyboard. I removed the heatsink assembly, and there was certainly no sticker on the processor or northbridge. I replaced the thermal pads with some thermal grease I had lying around (Zalman), but it didn't make much of a difference. It might take a little longer for the fan to speed up, but once it's running it basically never stops even though the processor is idle.That's just not acceptable for a CPU with 10W TDP!
I think part of the problem might be that there is no dedicated intake for the fan, so it's trying to cool the processor with air that has been heated by other parts of the system. imparire might be on to something!
You would think the fact that many users go so far as to disassemble their computer, voiding warranty and risking breaking it, would alert Lenovo that this is a serious issue!
06-07-2010 12:54 PM - edited 06-07-2010 01:01 PM
I am thinking about two more things and tests now:
- I may drill one more hole in my PC,
- then I will compare temperatures at 100% CPU load, with open holes or a piece of tape covering those holes.
A piece of tape should allow me to confirm if those holes do or not make a real change for the same room temp. My answer will follow next saturday. But a fresh air intake close to the fan should mak a difference.
It really depends of how air flows are inside this PC, without the holes I added. Without extra holes, even USB ports are fresh air intakes.
06-07-2010 02:11 PM
I measured the load temperature with and without the keyboard in place (removing the keyboard gives free airflow to the top side of the fan). The difference was about 10C.
Another interesting fact: On the inside of the chassis, under the fan, there is a pattern in the plastic. The pattern is the same as the ventilation holes by the memory slots. But for some reason Lenovo decided not to cut out any actual holes!
06-07-2010 03:15 PM - edited 06-07-2010 03:46 PM
Weiman wrote I measured the load temperature with and without the keyboard in place...
I wanted a laptop, not a tablet, I'll keep this PC with its keyboard
According to what you noticed, I'll definitively drill one more hole and make this test, with or without tape, to measure the CPU temp difference at null, half and full load. I can do this next saturday only.
Drilling into may not be the best solution - especially for waranty - but I prefer lower CPU temperature. CPU will last longer, fan should run slower, maybe a little bit less, less at higher speeds, this sparing also the battery.
...under the fan, there is a pattern in the plastic
I see the same on my own pictures and PC, added earlier. But care because later, another issue will raise.
I had to open a Toshiba (many other laptop have the same issue, this isn't a brand issue), to remove the dirt, after a year of - heavy - usage only. If you take a look at this picture, you will notice a similar cooling system, with a heat pipe/sink at the left of the PC and holes just below the fan, you will also see what it sucked in a year... and you will see much biger heatsinks, I added also a Fujitsy laptop parts picture on the same forum page:
06-11-2010 02:31 PM - edited 06-11-2010 03:44 PM
I tested a version 2 patch, with 3 more holes. I added those new holes much in front of the fan.
After 15 minutes system heatup with heavy activities (CPU, disk, etc), with the CPU running most the time at 100%, I rebooted the PC to kill all my processes. After system startup, CPU temp was finally back to 41°C for a room temp of approx 24-25°C.
Then I increased again CPU load, with my version 2 patch:
- 50% CPU load: temp reached 51°C
- 100% CPU load: temp reached 58°C, fan maintained that same CPU temp
- back to almost 0% CPU use: temp reached again 41°C, within approx 10 minutes
After that, CPU only slowly reached again lower temps (at 24-25°C room temp). Fan remained active, but at its lowest speed.
From 41°C and a 23-24°C room temp (room temp decreased a little bit), I rebooted again the PC and I "unpatched" that box using tape, to cover those holes:
- after system startup, the CPU was at 45°C, not at 41°C...
- then I increased again the CPU load,
- 50% CPU load: temp reached 54-55°C,
- 100% CPU load: temp reached 62°C, this is close to the max I measured last week, without any patch, for almost similar room temp
At 100% CPU load, I repatched the box, removing the tape over those holes. temperature decreased then only slowly to 59°C... Once this PC is really heaten up, it seems that it is more difficult to cool it down again.
Back to 0% CPU load, without system reboot, for 23-24°C room temp... My box was warm under my left hand (the CPU). After long minutes at almost 0% system load, CPU was still at 43-44°C and the fan was running continioulsy, at lowest speed.
From that point, with version 2 patch, I loaded again the CPU to 50%: 52°C only, but with a really warm box. Then I raised again CPU load to 100%. 57... 58°C... even 59°C.
It seems that some small holes in this box, just under the fan, can decrease CPU temp by approx 3-4°C. CPU temp decreases also much faster when its load decreases again.
After several minutes again, the PC was back to lower temperatures. I notice now 41 to 47°C, for my usual activities (an average of 10 to 20% CPU load, peaks at 70%), fan then mostly running only at its lowest speed, for a room temp at approx 23-24°C. Higher fan speeds do now only kick in shortly, during real system/CPU activities or loads. I do prefer this PC patched, drilled or punched that way, much cooler and quieter.
A picture of my version 2 patch and the tape I used for those tests; I'm comparing the U350 noise level and cooling system to a Rseries laptop which is also running Linux, for similar usages and room temperatures:
06-13-2010 09:01 AM
i give up guys. lenovo's support has be dissapionting at best.
I would recommend the dell v13, it has similar specs (core 2 duo ULV, 13.3", slim) BUT hey what do you know...no FAN/HEAT issue! I just bought one and I am glad i didnt wait any longer for a fix on the u350.
sorry lenovo, this is how you lose potential customers.
06-13-2010 09:58 AM
According to what I see here, this Dell V13 has holes close to the fan, in the bottom of its case:
This makes a difference, I notice it with my own patch.
Now I would like to slow down the fan, at its lowest speed; this would decrease the noise level. For the time being, I couldn't find any ACPI/software solution, I was just able to dump corresponding registers.
06-13-2010 04:21 PM
Some pages back a Lenovo admin called Mark Lenovo said that Lenovo acknowledged the issue but needed a U350 showing the issue. He asked if someone from USA could lend his U350 to the development team at Lenovo.
As far as I know, every U350 has the loud fan issue, but the perception of the issue varies from owner to owner, so I can understand Mark`s request.
To make it short: Can a volunteer lend his U350 so Lenovo fixes it for us all? It would be most appreciated.
06-14-2010 11:41 AM
alymenbr wrote To make it short: Can a volunteer lend his U350 so Lenovo fixes it for us all? It would be most appreciated.
I'm sorry, I'm out the US. I'll have a last suggestion, from my investigations and comparisons.
Many other laptops and desktops are louder, most of those being "entertainment" computers. Music and video sounds often cover their fan noise. This can explain why many people are satisfied by the current bios and fan behaviour.
Earlier, others suggested that the fan should only kick in at 55°C or more. Is the fan speed fully controlled by the bios? If yes, the fan could be switched on from 40°C, but at a much lower and unaudible speed. This would help "passive" or silent cooling, for lowest CPU activities. Fan could then switch to higher audible speeds at temperatures above 55°C only. This would be more close to everyones expectations and close to silent laptopts, at common room temperatures.
I now just recall what alymenbr just wrote... Some pages back a Lenovo admin called Mark Lenovo said that Lenovo acknowledged the issue but needed a U350 showing the issue. He asked if someone from USA could lend his U350 to the development team at Lenovo.