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-   -   Intel Xeon PHI? (https://www.mersenneforum.org/showthread.php?t=25767)

 kruoli 2020-08-03 17:13

2 Attachment(s)
Here are my results of the disassebly: Only two screws to loosen, but the remaining parts cannot be "blown on". The wind tunnel is closed. In order to open it, I'd have to bend the fins and I'm not comfortable doing this.

 masser 2020-08-03 18:19

How large is the area on top? Could you secure a large (200 mm) fan on top that would draw air through the gaps in that heatsink?

 kruoli 2020-08-03 18:45

92 [$]\cdot[/$] 246 mm (total area).
76 [$]\cdot[/$] 220 mm (only the fins).

My only 200 mm fan is quite slow and would overlap my Phi by a bunch. Maybe two or three 80 mm? But I doubt that any fan could suck enough air through those very tightly fitted fin tops.

 ewmayer 2020-08-03 21:02

Thanks for the pics, now I finally have a good sense what we're dealing with, colling-options-wise. As a short-term nondestructive half-measure, setting it crosswise in the airstream from a corded desktop fan [url=https://www.amazon.com/gp/product/B001R1RXUG/]like I use to help cool my 3-Radeon-VII desktop cruncher[/url] couldn't hurt, just see how rapidly temps spike under load and how bad the resulting throttling is.

But what this beast really needs is a larger version of the kinds of centrifugal-ducted fan in a U-shaped enclosure one finds in laptop and other compact compute devices. Something [url=https://www.amazon.com/Soplador-radial-centrigual-sin-escobillas/dp/B01CSNEO2G]like this[/url], just of the closest size you can find to match the dimensions of the rectangular opening of the finned end of your card, to minimize or eliminate the need for any custom adapter-ducting segment.

 kriesel 2020-08-04 00:03

7120A uncovered

3 Attachment(s)
Fan housing is cast metal in this unit.

 ewmayer 2020-10-27 19:54

Quick update - the wares on offer by the eBay seller linked in the OP are all gone, but the specific model of Phi in question was an older [url=https://en.wikipedia.org/wiki/Knights_Landing_microarchitecture]Knights Corner one[/url], which supports a flavor of 512-bit SIMD, but not AVX-512. For that you need a Knights Landing, which means a 72**-model Xeon Phi, and those tend to be both harder to find in the aftermarket and pricier, [url=https://www.ebay.com.au/itm/Intel-SR2X5-Xeon-Phi-Processor-7210F-64-core-32MB-cache-nice-/153512705068]even in copro form[/url].

If someone spots one for under US$500, tho, by all means send up a flare. Could be an interesting mini-build project for next year.  EdH 2020-10-27 19:59 [QUOTE=ewmayer;561277]. . . If someone spots one for under US$500, tho, by all means send up a flare. Could be an interesting mini-build project for next year.[/QUOTE]

[URL]https://www.ebay.com.au/itm/Intel-Xeon-Phi-Processor-7210F-1-30Ghz-64-Core-SR2X5-867304-001/293687842505[/URL]

 ewmayer 2020-10-27 20:15

[URL]https://www.ebay.com.au/itm/Intel-Xeon-Phi-Processor-7210F-1-30Ghz-64-Core-SR2X5-867304-001/293687842505[/URL][/QUOTE]

[I snipped all the link-tracking crud from your URL] That's just the bare CPU ... and I just realized that my "pricier" link is also bare-CPU-4-sale. So your bare-CPU is a far better deal than the one I linked to, but in any event we need the pci-e coprocessor version, which looks like the one linked in the OP, just with a newer KNL-version CPU.

 EdH 2020-10-27 20:25

[QUOTE=ewmayer;561280][I snipped all the link-tracking crud from your URL] That's just the bare CPU ... and I just realized that my "pricier" link is also bare-CPU-4-sale. So your bare-CPU is a far better deal than the one I linked to, but in any event we need the pci-e coprocessor version, which looks like the one linked in the OP, just with a newer KNL-version CPU.[/QUOTE]
Thanks for the info and the help with trimming the URL. I did try to figure it out, but couldn't. I'm going to look at the two and maybe I'll understand the "URL extra crap (crud) better."

Edit: OK, I didn't even recognize "trkparams.":redface:
I will try to be more attentive. (Original URL trimmed.)

 VBCurtis 2020-10-27 21:33

I've noticed these bare CPUs on ebay on occasion, but have never found a matching motherboard for a reasonable price, or even clearly and obviously compatible.
What boards work? I mean actually for sale, I've found a model listing but not a for-sale offer of the models I've seen that claim Phi compatibility.

On the used market, why would there be a supply imbalance between used CPUs for sale but not their corresponding boards (fried motherboards are a possibility, but seem unlikely for kit in this category)?

 M344587487 2020-10-28 10:44

The standard 2nd hand server market has a lot of CPUs because companies often start with a low end configuration for a socket and upgrade to a high end configuration down the line as a cheap upgrade path. At least that's what I attribute it to.

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