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Old 2020-05-21, 18:45   #243
ewmayer
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Quote:
Originally Posted by preda View Post
I think something like this is what you want:

https://www.amazon.com/6-Pack-Graphi...0035671&sr=8-2

(I'm not endorsing this particular instance, you should shop around, this is just an example)

You get 6x for $30, and the USB cable is easy to route. The downside is, you need to power this adapter (more power cords). Also be sure to set the PCIe to Gen1 on the motherboard, as these extendenders don't handle Gen3 usually.
Yes, same thing occurred to me first thing out of the bed this morning ... was just looking at this (single-riser, $4.99) and this other 6-pack ... I think the 1-item cheapie should suit my current needs.

What kind of power cable do these need?Zooming in on the pics of the above, I see it's a 6-pin peripheral&sata power cable - yah, not pretty, but "function first, form second".

The other thought I had this a.m. was, if I'm going to mount card3 away from the 3 pcie x16 slots, why not move card2 into the slot farther away from card1, the end-of-board one originally intended for card3? Much better airflow to card1 that way, and would give easier access to both one or more of the 3 pci x1 slots on this board, as well as to the middle full-length slot, currently holding card2. [By way of visual reference, the mobo block diagram is attached below - currently cards1 and 2 are in the 2 full-width pcie slots nearest the CPU, it would be nice to move card2 from the middle slot to the bottom one]. If I were then to use the full-length slot for the riser, that would obviate the Gen1-vs-Gen3 issue, wouldn't it? The one thing that would be needed, however, would be a full-width riser cable in actual circular-cross-section cable form, as opposed to the wide lasagna-style ribbons that seem to be the default option for full-width riser extensions.

One more thing is needed to move card2 into the bottommost pcie slot - a low-profile power/reset-switch bundle. The plastic plugs on my current one stand 3/4" high, which interferes with plugging a card into the bottommost pcie slot. I trust/hope such a low-profile (or perhaps right-angle) switch bundle is available?

Note that using a pcie extension card is the obvious solution here, but that is a bad option for me since the GPU mounting brackets that come with the test-frame I'm using as a chassis only work on cards plugged directly into the pcie slots on the board. Plus, one GPU sticking up like a sore thumb? What kind of aesthetics is that? :)
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Old 2020-05-21, 23:42   #244
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Update: Turns out I was able to use pcie slot #3 (farthest from the CPU, next to long row of pinouts at edge of mobo) with the existing power/reset switch bundle, just had to smush the little cables sticking vertically up from the latter to the side at a right angle ... not pretty, but works fine. Pic attached - the spacing between the 2 cards is now ~2.5", compared to 1" before. With the extra spacing it'll be much easier to access the short x1 pcie slots between the 2 cards to plug in the mobo-side riser cable plug. The improved airflow is allowing me to run both cards at sclk=4 (--> total draw 600W) while I prepare for card3 over the coming days. The latter card will go into the gap between PSU and card1 you see in the pic.

In order to mount card3, on the back side ('R' side of the RADEON-spelling LEDs) I'll screw the 2 ends of the L-shaped bracket into vertical Alu. supports which I'll craft this weekend. On the front side it was less obvious how to proceed here, but a close look at the card reveals those 4 little holes running vertically down from the two 8-pin power plugs in each card to be threaded for the same kinds of screws one uses to attach the card mounting bracket to e.g. an ATX case. so I should be able to run a pair of additional thin-rod Alu. supports at the needed angle from the metallic-red test frame up to the 2 bookend screw holes of the quartet in card3. It will necessarily look rather jury-rigged, but airflow to the whole setup will be excellent, and the top-mount card will serve the added purpose of keeping dust off the mobo around the CPU.

And I will still have the option of adding a 2nd R7 to my Haswell system using the 8-pin power-cable splitters I ordered a couple days ago, should I feel really ambitious and wanting a 5th R7. It's quite addictive, I tell ya. :)
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Old 2020-05-22, 01:58   #245
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Wow, these cards are ridiculous. Is any place selling them at close to the original $549 price tag?

Quote:
Originally Posted by axn View Post
it sits around high 400s/low 500s
Quote:
Originally Posted by kriesel View Post
Some log analysis here indicates 340-440.
Or are they selling anything similar since it was discontinued? The Radeon VII Pro is out of my price range ($1899), but how are they expected to compare?

https://www.amd.com/en/press-release...ii-workstation
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Old 2020-05-22, 03:03   #246
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Wow, these cards are ridiculous. Is any place selling them at close to the original $549 price tag?
You could still get them for that (subject to daily fluctuations in a $550-600 price band) not too long ago on Amazon, which in my case with CA 8.5% sales tax would've meant $600. None in stock there since about a month ago, and I see cheapest there via a reseller is a massive $850. (However, 10 top-end quad CPUs plus PSUs/mobos/memory/chassis would cost a hell of lot more, so in per-GIMPS-throughput terms...)

I had forumite and eBay/Radeon maven PhilF keeping a lookout for me, mid-April he alerted me to a seller putting 3 used ones (which looked very clean, if you believed the pics) up for sale there, including sales tax and $20/each shipping I paid $1560 total, $520 each. They arrived looking basically new and all work great, no noisier-than-expected fans or anything, so that was a damn good deal at that date.

If you're interested, either set a watch on eBay or PM PhilF, he seems to have some magic mojo with finding these there at good prices.

OTOH, perhaps my posting sexy-build pics and the attendant yuuuge througput numbers here has caused a bunch of our fellow MFers to rush out and scarf up the remaining available-at-not-usury-price stock. :)

Good luck, by all means post here if you manage to find one at a decent price.

Edit: Just rechecked Amazon.com, now have "In stock on 8 June", $594.44 & free shipping. With new stock coming, that price might dip a bit lower, but unlikely under $550. If one orders one today and the price drops between the order date and ship date, I don't know if one can claim the lower price ... I guess one could simply cancel the initial order and order another at the lower price.

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Old 2020-05-22, 20:31   #247
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@ewmayer

Thanks for the reply. I'll keep watch on Ebay/newegg/amazon etc. Your build posts definitely got me interested! But given that prices are so high, I will wait. Probably doesn't make sense to buy a new space heater right before the summer months anyway.


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Edit: Just rechecked Amazon.com, now have "In stock on 8 June", $594.44 & free shipping. With new stock coming, that price might dip a bit lower, but unlikely under $550. If one orders one today and the price drops between the order date and ship date, I don't know if one can claim the lower price ... I guess one could simply cancel the initial order and order another at the lower price.
They must be sold out already. It's showing $799 on my end.

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Old 2020-05-22, 20:50   #248
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Quote:
Originally Posted by Runtime Error View Post
They must be sold out already. It's showing $799 on my end.
Indeed - damn, that was quick. The lesson is, for those in the market for an R7, check availability/pricing several times a day, and don't hesitate to grab one or more if the price comes into range. I was actually tempted to snap one up a few hours ago at $550 for the one remaining space in my Haswell ATX-case system, but figured that would be a Cry For Help worthy of entering a 12-step program. :)

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Old 2020-05-22, 22:16   #249
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Quote:
Originally Posted by ewmayer View Post
I was actually tempted ... but figured that would be a Cry For Help worthy of entering a 12-step program. :)
A gpu is just a component. Don't you stock spare components?
Quote:
that was quick
One can save a lot of money by strategic procrastination. These offers sell out literally overnight, if not quicker. "You snooze, you lose."

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Old 2020-05-22, 23:30   #250
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Quote:
Originally Posted by kriesel View Post
A gpu is just a component. Don't you stock spare components?
An extra car in your driveway is just a component. Don't you stock spare components?

Seriously, to justify a $500-plus 'spare', said component better be mission-critical. One of my R7s conking out would (will) be annoying, but nowhere near disastrous. My 10-year-old Macbook - for which I *do* have spares of all imporant components, including ready-to-go-just-swap-in-my-HD spare and a regularly updated cloned SSD of my installed spinning-disc HD - *that* conking out w/o a spare available *would* be a disaster.

Quote:
One can save a lot of money by strategic procrastination. These offers sell out literally overnight, if not quicker. "You snooze, you lose."
Indeed - I strategically procrastinated for years, and now I save tons of $ by no longer needing to buy a high-end-CPU for my crunching. New-build is a nice mobo but with a cheapie Celeron dual-core CPU, I can build code on it but it would be a waste of Watt-hours to use it for dedicated 24/7 crunching.
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Old 2020-05-23, 04:39   #251
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Quote:
Originally Posted by ewmayer View Post
I strategically procrastinated for years, and now I save tons of $ by no longer needing to buy a high-end-CPU for my crunching. New-build is a nice mobo but with a cheapie Celeron dual-core CPU, I can build code on it but it would be a waste of Watt-hours to use it for dedicated 24/7 crunching.
When I first built my dream machine, my thoughts were to build one every other year expecting decent improvements with Intel's Tick-Tock strategy. Alas, Intel crapped with no real improvements over the last 6 years.

The Radeon VII is so far ahead of every competitor (both CPU and GPU) that I am confident there will be no comparable hardware offerings from a $/iter standpoint, either CPU or GPU, over the next 5 years that it makes sense to buy as many Radeon VIIs as one's budget allows. It is truly a game changer.
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Old 2020-05-23, 18:34   #252
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$649 on Newegg. Not exactly a steal, but if you act fast it comes with an Xbox Game Pass for PC!

Quote:
Originally Posted by Prime95 View Post
The Radeon VII is so far ahead of every competitor (both CPU and GPU) that I am confident there will be no comparable hardware offerings from a $/iter standpoint, either CPU or GPU, over the next 5 years that it makes sense to buy as many Radeon VIIs as one's budget allows. It is truly a game changer.
Is there no hope that they produce a similar GPU in the future? (They call it their Vega20 architecture, I think). The Radeon Pro VII is expected to go for $1,899 but have almost twice the double precision performance of the Radeon VII at less wattage. Is it too expensive to be a contender?
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Old 2020-05-23, 18:48   #253
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Quote:
Originally Posted by Runtime Error View Post
Is there no hope that they produce a similar GPU in the future? (They call it their Vega20 architecture, I think). The Radeon Pro VII is expected to go for $1,899 but have almost twice the double precision performance of the Radeon VII at less wattage. Is it too expensive to be a contender?
I amend my statement that in the bang-for-the-buck consumer card market, you won't see anything better for 5 years.
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