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Old 2020-05-23, 19:18   #254
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Quote:
Originally Posted by Runtime Error View Post
$649 on Newegg. Not exactly a steal, but if you act fast it comes with an Xbox Game Pass for PC!

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?
Radeon VII was a stop-gap before Navi was released, they won't re-release it or a Vega20 successor for consumers. RDNA is the future of the AMD consumer GPU line, unless they accidentally add a few zeroes to the next Vega20 run we're out of luck.
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Old 2020-05-23, 19:29   #255
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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 was under the impression that the R7 *was* the first major consumer iteration of Vega20 - see the thread next door which introduced it. "Almost double the DP" means the Pro is a worse deal bang-for-buck-wise than the R7 at any price > $1000, ignoring the lifetime-power costs, which is of course an important part of the true price-optimization problem. I'll let some of our lifetime-system-cost mavens do the number-crunching but factoring in the power savings over (say) and expected 5-year usable lifetime, the Pro may in fact come close. But the R7 may still end up as an example of "it took a full 5 years from its release for something else to beat it."

Cleaned up my mini-workbench this a.m. in order to pull the drill press out into a working position, in preparation for crafting the custom brackets I need to mount the 3rd and final R7 in my my new test-frame system build. One of the things I miss from my old Cupertino digs was a covered (via upstair neighbors' balcony) patio, to keep my tools and use as a work area: In summer 2016 I spent a month building Ernst's dream workbench from a pile of scrap lumber I'd accumulated in a corner of that over the years, nice super-solid wood frame, 2 x 5" top work area, shelving underneath to hold various boxes of accessory tools, weight ~80 lbs. When I moved to the north SF Bay 2 years later I was forced to downsize it to 2x2" work area in order to not take up too much room in my large-but-shared apartment. So now whenever I have any serious work to do I gotta shuffle stuff around.

Oh, getting back to the "grab 'em whenever you can" theme, perhaps we could crowdsource things in form of "a Radeon VII price-whisperer" club, anyone spotting one for < $600 post alert here. I would even be amenable - since GIMPSers live all over the world - to having those wanting one or more post that here, if one of their fellow price-watchers spots one (or however many are wanted), they grab 'em up (virtually), then when the wanter paypals the grabber-upper, the latter switches the ship-to address to that of the wanter. For example, say George and the wife decide to resume their Covid-19 Asian Contagion mega-cruise of early this year. Before leaving, George indicates here he is interested in acquiring 2 more R7s at price < [whatever], in [new|used] condition. A few weeks later, I happen to spot fresh stock at Amazon in the desired price range. I buy, PM George, he paypals me 12 hours later, I login to my Amzn account and switch ship-to address to whatever he tells me.

Several obvious technical issues arise here:

o International shipping vastly complicates things, might require some kind of regional or by-country "buddy system";

o In the above example, if by the time George pays me the items have already shipped, that means extra time/expense for me to re-ship to him;

o If wanter changes mind and stiffs the grabber-upper and in the meantime the items have shipped, the latter at best faces the hassle of a return, or (e.g. for eBay, with a 30-day "return only permitted if item not as advertised" item) ends up holding the gear. Sure, odds are good of being able to sell the gear on to another wanter, but extra time/expense/hassle even in that case.
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Old 2020-05-23, 20:12   #256
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Quote:
Originally Posted by Runtime Error View Post
$649 on Newegg. Not exactly a steal, but if you act fast it comes with an Xbox Game Pass for PC!
I had an Asrock. It lasted 3 weeks before it became "prevent boot in any system it's installed in." dead.

Quote:
Originally Posted by ewmayer View Post
"Almost double the DP" means the Pro is a worse deal bang-for-buck-wise than the R7 at any price > $1000, ignoring the lifetime-power costs
...
2 x 5" top work area, shelving underneath to hold various boxes of accessory tools, weight ~80 lbs. When I moved to the north SF Bay 2 years later I was forced to downsize it to 2x2" work area
...
Sure, odds are good of being able to sell the gear on to another wanter, but extra time/expense/hassle even in that case.
Here, utility rates make the computation easy; 1 watt-year ~$1 after sales taxes.
Comparing list prices, $1849 vs 699, 6.5 TFlops vs 3.5, 250W vs 300W nominal, probably accurate wattage after allowing for PSU losses, spread over 3 year useful lifetime. (By then we'll be coveting some new hardware, or the PCB will have shorted and charred months after the warranty expired; ala RIP my GTX1070.)

Radeon Pro VII
$1849
3x$250 =750
2599
/6.5 = $400/Tflop-year

Radeon VII
$699
3x$300=900
1599
/3.5 = $457/Tflop-year

Adjust power cost up or down according to whether air conditioning cost or heating benefit applies and whether you or the landlord are paying utilities. Last time I ran the numbers here, an 85M PRP cost $1.01 in the heating season, $1.17 neutral, $1.51 with air conditioning handling the waste heat at 10. EER, 2.93 COP and 4-year straight-line amortization of a $600 Radeon VII. Once you buy the gpu, it's sunk cost. Marginal cost is $0.64, $0.806, $1.14 /85M PRP for the 3 cooling cases. These would all be a bit better now because the code has been further optimized.

2x5", 2x2"? check your units, or are you a jeweler to unwind? ;)

I think some eBay used Radeon VII sellers are like ticket scalpers. There are frequently used gpu listings for hundreds of dollars higher than new list price.

Last fiddled with by kriesel on 2020-05-23 at 20:45
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Old 2020-05-23, 23:35   #257
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Thanks for the costing-out, Ken ... so close enough that there's no compelling reason to wait for the Pro if you have a chance to snarf up a new(ish) R7 now for < $600, but once the Pro hits shelves those will be an attarctive option for those willing to shell out big $ now to save on the lifetime cost down the road.

The one possible good reason I can think of to prefer 2-3 R7s over 1 Pro is "distributed failure" - if one of my 2 or 3 R7s dies, it's less impactful than my single Pro going boink.

On new-build front for me: splitter cabling in and successfully powering the 2 currently-installed R7s. Locally (right at the GPU) it's uglier than before, but globally, having one less long ribbon cable running from GPU-to-PSU is nice. More importantly, it tells me that installing a 2nd R7 in my Haswell system is an option with the existing older PSU, which has just enough PCIe 8-to-dual-8 power plugs for a single R7. As noted before, the dual-R7 Haswell would need to run those @sclk=3 (vs current sclk=4) to limit both the power draw on the PSU and keep heat inside the open-side ATX case manageable. (Hmm, in the context of the above, I now start to think a Pro as a 2nd GPU next year as opposed to looking for another R7 this year... :)

And Alu. front mounting bracket for the above-CPU floating GPU mount is done, bent into proper shape (final pics later will show why this was needed), holes to attach to test frame and middle 2 holes of the little quarter-row on the power-plug-side of the R7 drilled and test-fitted. I said earlier that those 4 holes in the side of the R7 housing have the same-gauge threading as a standard PCI-device mounting-plate screw for an ATX case, but that proves not so - they are similar diameter but quite a bit finer threads. But some of the leftover little screws from the test frame trn out to be exactly the needed gauge.
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Old 2020-05-23, 23:44   #258
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News Flash: Just happened to reload the XFX R7 page on Amazon after posting above, saw 3 like-new on sale from a reseller, $490 plus $4 shipping each, with CA sales tax I paid $1600, or $533 each including shipping. Snarfed all 3 up - who wants one (or more)? Hopefully I can simply fiddle the ship-to-addresses to reroute as needed. (Worst-case each would need reship in a USPS medium flat-rate box, $15 domestic cost.)

[Note: oddly, page still shows "Only 3 left in stock - order soon." Maybe until the payment clears?]

[Edit: Aha, now page-reload shows $760 plus shipping ... I could make a small profit here, but I wouldn't do that to a fellow GIMPSer.]

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Old 2020-05-24, 02:16   #259
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Double the TFLOPS means nothing. R Pro VII has the same nominal memory bandwidth as R VII. Actual gains could be much smaller (depends on how much stable it is at higher mem clock settings).
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Old 2020-05-24, 04:34   #260
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I also doubt you get double the TFlops for only 50 watts. Plus, you may have to lower the clock rate to deal with the heat.
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Old 2020-05-24, 04:46   #261
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Quote:
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I also doubt you get double the TFlops for only 50 watts. Plus, you may have to lower the clock rate to deal with the heat.
AMD's specs are 50 watts *less*, for the Pro.
See, for example, https://www.anandtech.com/show/15777...radeon-pro-vii about half a page down for a handy chart of flops and features.
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Old 2020-05-24, 05:53   #262
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AMD's specs are 50 watts *less*, for the Pro.
That would be *very* surprising.

Radeon VIIs do not achieve 3.5 TFlops in homes. They throttle due to heat well before then. I don't see how a Pro model works around this problem.

I won't be a buyer at that price, but I'm curious as to what the differences will be.
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Old 2020-05-24, 07:52   #263
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Quote:
Originally Posted by kriesel View Post
Radeon Pro VII
$1849
3x$250 =750
2599
/6.5 = $400/Tflop-year

Radeon VII
$699
3x$300=900
1599
/3.5 = $457/Tflop-year
If we assume that effective thruput scales with rated TFLOPS, Ken's analysis shows that buying 1 Pro is slightly better than buying two non-Pro (slightly less thruput, but better lifetime cost). If we consider a period of 5 years, then it gets even better in Pro's favor.
Of course, like I said, I doubt this will actually pan out. PRP testing is generally memory bottlenecked, and so in practice, the Pro might achieve 1.3x thruput. Also, the current sweetspot of non-Pro involves underclocking, so the TDP figures are also not the best ones to use for this calculation.
Nonetheless, it /is/ compelling enough that we should get hold of one to understand the actuals. Even if it doesn't beat the non-Pro in outright value, it still might be better than everything else out there -- with the added benefit that this will actually be in stock.

BTW, Ken, you forgot to divide by the number of years for your TFLOP-year figure.
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Old 2020-05-24, 11:44   #264
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Quote:
Originally Posted by axn View Post
Ken, you forgot to divide by the number of years for your TFLOP-year figure.
Uggh. s/year/term/. My engineering professors would not approve, if they were still alive. The whole thing is just an approximate comparison anyway, since,

a) we don't often pay original list price,
b) utility rates vary considerably by location and somewhat versus time,
c) useful lifetime can vary too,
d) sticker shock for the Pro is a real barrier for some. TCO per unit theoretical or achieved throughput is one thing (or two or 4), but paying noticeably more for a gpu than the purchase cost of my first 3 cars combined is a hard sell psychologically
e) memory constraint on achievable throughput concern
f) TDP varies, and some users put a lot of effort into varying that, changing the utility cost faster than the throughput

Last fiddled with by kriesel on 2020-05-24 at 11:57
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