cooling dual xeon 5148 (passively).. help?!

[hongs]

Hi everyone..

this is my first post on the forums.. and i recently started putting my home PC together. specs are..

Dual Xeon 5148 (stock speed) passively cooled by supermicro SNK-P0025P coolers.
I have 3x120mm (Noctua 1200rpm fans).
The motherboard is a Tyan S2696.

I have a chenbro SR-107 case.. and there seems to be a lot of space (all rounded cables), but my temps according to speedfan is idle 58C.. and when I put 100% load on the cpus (via CPU burn-in), the temp goes all the way up to 83C. Is this normal?

When I open the side panel.. idle temp drops to 44C.. full load temp goes to 65C.

I tried creating some duct work.. but i guess my skills with cardboard and scissors ain't like when I was in grade 1.

Are the Noctua fans inadequate to cool this? I have the original delta 120mm AFB1212SHE that came with the box.. but they are noisy.. and I would like to keep this as quiet as possible.

I do have 8xU320 scsi drives in there too.. so the intake may not be the freshest of air.

Any help is appreciated.. thanks! I will try to post some of the actual system so you know the cable layout.

[hongs]

Here is a pic from a website as to how the internal looks like..

[Lyshen]

One problem I believe I see is you don't have enough air circulation. This is evident by the temps when you have the case open. With 8x U320 drives, they generate quite a bit of heat as well as block off the air flow into the case.

I'd assume that all 8x U320 drives are in the mid and lower bays? Do you have anything in the upper bay? Optical drive? If not perhaps get a Scythe Kama bay for fresh air intake?

And yeah, pictures would help.

[hongs]

One problem I believe I see is you don't have enough air circulation. This is evident by the temps when you have the case open. With 8x U320 drives, they generate quite a bit of heat as well as block off the air flow into the case.

I'd assume that all 8x U320 drives are in the mid and lower bays? Do you have anything in the upper bay? Optical drive? If not perhaps get a Scythe Kama bay for fresh air intake?

And yeah, pictures would help.

Hi Lyshen.. thanks for a quick reply.

yes.. the 8 drives are in the hotswappable bays.. and the is currently two of the three 5.25" external bays being occupied. One dvd drive, the other a tape drive.

i have the tape drive disconnected at the moment (did not get a scsi cable yet to chain up to it).

Thanks for the suggestion on the Scythe Kama bay fan.. it does look like it will take up three bays tho.

[hongs]

Hi everyone..

As promised.. here are pics of the actual system with the cooling issue. The system is not noisy (the drives are.. but that's ok).





additional hardware that I have not mentioned before are;
1. 8800GTS for a video card.
2. a PCI-X Dual Channel U320 RAID card
3. PC Power & Cooling Silencer 750Q power supply.
4. ram is FB-DIMM and I got 4 sticks in there.
5. optical drive is SATA.

Sorry if the pics are too small or too large.. i am not sure what the etiquette is for pic sizes on this forum.

Any info on how to cool this would be great. Thanks!

[born2code]

Those heatsinks seem awfully small by SPCR standards.

[hongs]

Those heatsinks seem awfully small by SPCR standards.

hehe.. yes they do, eh? Unfortunately.. I need LGA771 compatible coolers. I was looking at getting Verax X21 coolers, but since I do not read german.. I can't figure out the specs on the website (and its not that easy to find in the US).

Since this are Xeon cpus.. i can't really stick a honking huge cooler with a 120mm fan on it... since i'll be bumping into the other socket.

[born2code]

I understand what you are up against. If you look back a few threads, you would see I have been asking essentially the same question.

[hongs]

I understand what you are up against. If you look back a few threads, you would see I have been asking essentially the same question.

Oh? I will have a read thru your messages then.. did you ever get your problem resolved?

What temps are you seeing on your Xeon chips?

[born2code]

Oh? I will have a read thru your messages then.. did you ever get your problem resolved?

No.

[jaldridge6]

you could also try the CM stacker case, its got slots for 4 120mm fans on the side. you could have the top two slots blowing at 1000rpms onto some passive coolers.

[jaldridge6]

http://www.extremeoverclocking.com/revi ... 830_4.html

[murtoz]

First of all, how are you measuring temps? As far as I am aware, these Xeon's use the same temperature sensors as the quad core conroes do, which makes 'old fashioned' temp measurement difficult. What I've seen this type of CPU report is a number of degrees below throttling point. Try the intel thermal analysis tool (tat) for accurate results.

If the 83 really is the temperature it is too high though. You should try to duct the cpu's. I believe those Noctua's spin rather slowly, they might have trouble pushing the air in between the heatsink fins.
From other dual Xeon systems I've seen, they duct the top fan to the cpu's, the duct drops from being level with the fan to being level with the heatsinks before it gets to them, so the air doesn't rush over the top of the heatsinks but actually goes through the fins (hard to explain in words - hope you get what i mean). You might want to consider extending the duct all the way out to the rear fan so you exhaust all the hot air (and you cool your memory too that way).

I do agree your heatsinks look small on the pics as well. How tall are they? Intel does sell some passive 2U heatsinks (http://shop.intel.com/shop/product.asp?pid=SIPS1065) but if yours are the same height they probably cool better due to the heatpipes I can see on the pics.

Nice system though! Wish I could afford Xeons and FBDIMMS

[hongs]

First of all, how are you measuring temps? As far as I am aware, these Xeon's use the same temperature sensors as the quad core conroes do, which makes 'old fashioned' temp measurement difficult. What I've seen this type of CPU report is a number of degrees below throttling point. Try the intel thermal analysis tool (tat) for accurate results.

I was using speedfan 4.3.2, and the Tyan System Monitor application.

I am unable to run TAT as I am running Vista x64 and for some reason the program just refuses to run (needs me to login as an admin, and I did).

If the 83 really is the temperature it is too high though. You should try to duct the cpu's. I believe those Noctua's spin rather slowly, they might have trouble pushing the air in between the heatsink fins.

I agree.. and I think that was a poor judgement on my part when choosing my case fans. I am going to ducting the fan, and see if that helps. If not.. i may have to sacrifice some noise and get higher CFM fans to get more flow thru the heatsinks.

From other dual Xeon systems I've seen, they duct the top fan to the cpu's, the duct drops from being level with the fan to being level with the heatsinks before it gets to them, so the air doesn't rush over the top of the heatsinks but actually goes through the fins (hard to explain in words - hope you get what i mean). You might want to consider extending the duct all the way out to the rear fan so you exhaust all the hot air (and you cool your memory too that way).

thanks.. i will try with a cardboard mock up I guess.. and if I want to get fancy.. I will see if someone can make this duct out of plastic or something. as i said.. workshop has been a long time ago for me. =)

I do agree your heatsinks look small on the pics as well. How tall are they? Intel does sell some passive 2U heatsinks (http://shop.intel.com/shop/product.asp?pid=SIPS1065) but if yours are the same height they probably cool better due to the heatpipes I can see on the pics.

Yes.. these are 2U heatpipe passive sinks from Supermicro. I must admit that they do not seem too daunting like some of the LGA775 coolers out there... I do have the box active sinks from Intel that i can try.

Nice system though! Wish I could afford Xeons and FBDIMMS

haha.. =) thanks... ain't a good system until i can get some decent temps out of this thing. haha. =)

Hong

[hongs]

you could also try the CM stacker case, its got slots for 4 120mm fans on the side. you could have the top two slots blowing at 1000rpms onto some passive coolers.

Thanks for the suggestion, however currently.. this case is new... and I wouldn't want to replace it with something else. Also.. what are the dimensions of the CMStacker? I thought this was a full tower case.. I currently am not in the position to buy another full tower case. I have a 17" high Chenbro Sr-107 server case. Also.. I have 8xSCSI drives (hotswappable ones too).. that I need to fit into the case. I understand that the CMStacker would provide this.. but I would need to get hot swap enclosures for it separately on top of its price tag?

Hong

[mentawl]

To me, looks like the main problem is gonna be the airflow impedance caused by having the bottom hot-swap cages fully occupied. The Noctua fans aren't designed for high static pressure, so are likely to be having trouble pulling fresh air through the restricted drive area.

You might be better replacing at least the two "middle" 120mm fans with some more powerful fans - maybe not quite High Output Deltas, but even a 120x38 Tricool or similar is likely to outperform the Noctuas in that kinda enclosure. Since the fans are "buried" a little in the box, it's unlikely to cause too much of an increase in noise.

Just my 0.02 .

Tom

[hongs]

To me, looks like the main problem is gonna be the airflow impedance caused by having the bottom hot-swap cages fully occupied. The Noctua fans aren't designed for high static pressure, so are likely to be having trouble pulling fresh air through the restricted drive area.

You might be better replacing at least the two "middle" 120mm fans with some more powerful fans - maybe not quite High Output Deltas, but even a 120x38 Tricool or similar is likely to outperform the Noctuas in that kinda enclosure. Since the fans are "buried" a little in the box, it's unlikely to cause too much of an increase in noise.

Just my 0.02 .

Tom

Thanks Tom.. I think i do need to look into some higher output fans.. tho noise level will increase.. I am sure I will be able to find a compromise.

Antec Tri-cool.. that pulls about 80CFMs @ 30db? Are there any other fans out there with those specs?

so now I got 3x Noctua fans.. haha.. I think I need to find a use for them then.. hehe.

Hong

[mentawl]

Well, frankly, any fan is likely to be quieter than an SHE Delta, with the exception of the EHE, heh. I believe the SHE 120*38 is about 152CFM? =x

I mentioned the Tricool because they come with that handy 3-speed switch, so if "Medium" speed was enough you could set it to that - or even just have the fan facing the CPUs on "High" while the lower was on "Medium", or some such combination.

Only other fans I can think of off the top of my head would be a coupl've 120*38 Panaflos/NMB-MAT or the slower Papst fans. I mention the 38mm depth fans mostly because they generally can overcome high static pressure better than standard, thinner 25mm fans.

If you check out http://www.dorothybradbury.co.uk/ and go down to the NMB-MAT FB-120-L1A, you can see the kinda thing I'm talking about. They're the "current" versions of the old Panaflo L1A fans, and they're generally quite well behaved. Can make a fair bit of noise at 12v, but (to my ears at least) it's a very "nice" noise - quite smooth, mostly airflow rather than bearing/motor noise. A simple internal/5.25" bay controller would let you control the fan speed if you decided you didn't need the full 12v all the time.

One thing to check might be the clearance on the "internal" fan cages - might be a tight fit for a 38mm fan. The rear one should be no problem though.

/stops rambling

Hehe, hope this is of some use.

Tom

[hongs]

Well, frankly, any fan is likely to be quieter than an SHE Delta, with the exception of the EHE, heh. I believe the SHE 120*38 is about 152CFM? =x

yes.. its definitely a lot of air coming from these fans.. very noisy.. but more air noise than bearing noise.

I mentioned the Tricool because they come with that handy 3-speed switch, so if "Medium" speed was enough you could set it to that - or even just have the fan facing the CPUs on "High" while the lower was on "Medium", or some such combination.

Ahh.. i tend to like to just set the fan to auto or the peak speed.

I guess I am kind of lazy that way.. hehe =)

Only other fans I can think of off the top of my head would be a coupl've 120*38 Panaflos/NMB-MAT or the slower Papst fans. I mention the 38mm depth fans mostly because they generally can overcome high static pressure better than standard, thinner 25mm fans.

I have seen papst.. i thought i was getting some good with the noctua fans.. unfortunately they don't push the 47cfm or whatever the specs are. I am assuming a 80cfm one will be sufficient... but its a hit and miss.. maybe get the fans from a store that will allow me to return it if its not what i want.

One thing to check might be the clearance on the "internal" fan cages - might be a tight fit for a 38mm fan. The rear one should be no problem though.

gotcha.. i will double check this... it will be a tight squeeze with the 38mm behind the drive cage I think.. i will have to do some measurements.

/stops rambling

Hehe, hope this is of some use.

Tom

Thanks so much for the help!

[mentawl]

The thing to watch is that there isn't necessarily a direct correlation between air flow (CFM) and static pressure ability when it comes to fans.

For example, you could have a 25mm thick 50cfm fan and a 38mm thick 50cfm fan, and they'd both perform identically in free air, more or less. However, put them in a situation with restricted airflow, and the 38mm will "lose CFM" less quickly than the 25mm, all other things being equal. The difference between 25/38mm fans is the most obvious difference in ability, but different fans can be designed differently too, even when they're the same size - blade shape, motor configuration...

I suggested 38mm fans just because of this reason. Honestly, with 8 u320 drives cranking away behind the bezel, I very much doubt you'd notice a pair of L1As even at 12v.

No guarantee, mind you .

Tom