Radeon VII @ newegg for 500 dollars US on 11-27

[ewmayer]

Originally Posted by M344587487

Phew, for a second I though you went with an FX CPU and was cursing that I don't log in more frequently. Any Ryzen is good for the right price, FX is to be avoided in general but especially if efficiency matters.

Since this build is intended as a host for multi-GPUs, each of will provide throughput an order of magnitude larger than the CPU, it's not as crucial - but yes, one also wants the best CPU one can find for one's $.

The bundle arrived Thursday - quite fast for ground shipping, even accounting for the fact that the 'from' state, Nebraska, is "halfway to California", the destination. Alas, several key accessory items - open-air test bench and SSD - I ordered around the same time which I need for the build are delayed until 3 weeks from now - quite possibly result of the Covid-19 global suuply chain disruptions.

[M344587487]

The throughput isn't so important for the CPU but the efficiency is. That FX heap of junk sucks something like 40 watts idling and something on the order of 150+ watts under load for worse-than-haswell performance, you're damned either way.

[ewmayer]

SSD arrived last week, remaining still-AWOL component is the open-air test bench. While I wait for that, been thinking about some kind of airflow-friendly protective enclosure, and perforated metal-mesh sheeting sprang to mind, for example this. These come in a wide variety of mesh styles and hole sizes.

Idea is to snip off rectangular corner pieces and then bend the remaining material into a 5-sided box-cage which will slip over the rig (with a smaller rectangular cut-out for the I/O-ports side of the mobo; I can drill and tap a few threaded holes into the test frame to affix the cage.

[ewmayer]

Originally Posted by ewmayer

So sub another $142 from my money-left-under-cap, leaving $1513 - that's gonna be a bit of a trick to get 3 Radeon VIIs. But we live in hope. :)

If not for CA sales tax, I would've managed it, too - thans to PhilF who alerted me to an eBay new listing, 3 XFX 16GB Radeon VIIs available at $460 each.

Just snapped 'em all up - same "item as described" buyer protection we previously discussed, so returnable-if-not-working. Alas, $60 shipping and 8.5% CA sales tax adds nearly $200 to the total, which nets to $1,557.30.

Compare to new-on-Amazon: the prices vary day-to-day, but $550 is the most-frequent baseline one, what I expected to buy at should that prove the best option. Free-ship, add 8.5% CA sales tax and subtract 5% from using my Amazon Visa card, nets to ~$1700, so I saved a not-huge $143. But I figure it this way - the shipping charge helps pay the salary of some hopefully-not-abused-like-Amazon-delivery-folks USPS employees, and my item payment goes to some non-hecto-billionaire-douchebag.

Hope my long-delayed test-frame chassis arrives as now predicted on 20 Apr, so I'll have a system ready to try the R7s out in! Thinking about the PSU, it's rated 850W, I decided to run lean because the prices for >= 1000W PSUs are significantly higher (at least when I did my looking on PCPartsPicker, they were), so I'll probably need to run the 3 GPUs at sclk = 3, one tick lower than I run my current single R7 in my ATX case system at. Anything over 600W total is likely to be pushing it, PSU-longevity-wise. Will be interesting to see if the max-total-throughput-without-exceeding-600W calculus will permit loading the CPU at all.

[PhilF]

Originally Posted by ewmayer

If not for CA sales tax, I would've managed it, too - thans to PhilF who alerted me to an eBay new listing, 3 XFX 16GB Radeon VIIs available at $460 each.

Congrats! Let me know when you fire them up, because that way I won't worry about why my lights just dimmed.

[ewmayer]

Originally Posted by PhilF

Congrats! Let me know when you fire them up, because that way I won't worry about why my lights just dimmed.

True story - in the summer between my senior year at U of Michigan - I had just graduated with a BSE in Aerospace Engineering - and starting graduate school the ensuing Fall, I had a summr internship at NASA Lewis (since renamed after the late Ohioan John Glenn) Research Center, a few miles west of Cleveland. Lewis was famous for having one of the largest supersonic wind tunnels in the world ("The 8-by-6-Foot Propulsion Research Tunnel at Lewis can push 150,000 pounds of air every minute across the test section at up to twice the speed of sound"). Pushing that much air at such high speeds requires a massive amount of electrical power - at peak the Lewis supersonic tunnel used 250MW, and literally would cause the lights across the entire surrounding Cleveland metropolitan region to dim. So like expensive-timeshare-mainframe users of yore, they tended to run it only in the middle of the night.

[LaurV]

Originally Posted by ewmayer

True story

Nice one, thanks for sharing! (I love stories like that, that you, RDS, Paul, and other people tell here).

[ewmayer]

Originally Posted by LaurV

Nice one, thanks for sharing! (I love stories like that, that you, RDS, Paul, and other people tell here).

Another funny from my NASA Lewis days I am sure you, like me, a "never let political correctness get in the way of a good joke"-er, will enjoy -- Lewis was (and is) noted for its very strong microgravity research program and attendant facilities. Said facilities include a specially-modified KC-135 tanker, the famous parabola-flying "Vomit Comet" aircraft, as well as a drop tower, basically a 600-foot-deep vertical shaft which can be evacuated of air. Dropping a small instrumented experimental module (e.g. containing a flame-producing gizmo and attendant measurement apparatus) from the top gives 6 sec of microgravity; the tower is also equipped with a finely-calibratable - you really, really don't want to overshoot here - catapult launcher at the bottom, which doubles the ug time to 12 sec for apparatus launched upward. For obvious reasons of geometry, the drop tower bears the unofficial name "The Martha Washington Monument."

[Mark Rose]

Originally Posted by ewmayer

Ok, first gpuowl issue - my Haswell system has always been notoriously unstable, I get the Linux equivalent of BSOD ~2x per week, no overclocking, either.

Try overvolting the CPU. I had a i5-6600 that started producing bad results about two years ago. It might be the motherboard, but it's not the memory or PSU in my case. But I think I've fixed it, by simply overvolting it by 0.02 volts.

Maybe AVX2 24/7 causes electron migration over time, who knows.

[ewmayer]

Originally Posted by Mark Rose

Try overvolting the CPU. I had a i5-6600 that started producing bad results about two years ago. It might be the motherboard, but it's not the memory or PSU in my case. But I think I've fixed it, by simply overvolting it by 0.02 volts.

Maybe AVX2 24/7 causes electron migration over time, who knows.

There is an overvolting menu item amongst the OC submenus in my Mobo BIOS, but it's not enabled ... but I did solve my instability issues another way, George suggesting disabling C-states, an Intel power-saving feature, been rock-solid stable ever since, current uptime 26 days. The CPU still throws occasional data glitches, but since I switched to PRP-only a couple months ago for that very reason, all cases which have shown >= Gerbicz-check errors along the way have been successfully early-DCed.

In other news related to the thread topic, the open-air Aluminum test-bench chassis I ordered around the same time as I bought the AMD Ryzen5 + Gigabyte-gaming-mobo + watercooler + RAM bundle from an ebay seller in late March as a basis for my multi-Radeon-VII build finally arrived a couple days ago, pretty much the same time the big box with the $1500 worth of R7s did. Been spending 2-3 hours every day since to get it assembled - final result looks nice, but really dumb design, 10x as many small parts and 10x as much assembly effort as needed. so finally got to the mounting-the-mobo stage a couple hours ago, after getting that done and everything properly aligned and the PSU installed, went to grab the RAM modules, only to find none at hand.

Partly my fault for not carefully doing an item-by-item checkoff at box-unpack time, but I'm sure I didn't overlook and accidentally discard them because I cut open both ends and flatten all boxes for recycling, plus I saved all the accessory boxes and packaging material, stuffed all the bubble wrap and put in my mailing-and-shipping-supplies storage area, figuring it would probably come in handy for my own Xmas packages later this year. Just went thoguh it all, and completely emptied out all the small accessory boxes (OEM CPU cooler, water-cooler accessories box, thermal-paste-syringe box), no joy.

Looking at the original item pics, I highlighted (red rectangle) that block of what looks like some kind of RAM-module to the right of the cooler - that's not in the stuff I received, MoBo has only the empty DIMM slots there. (This is basically a copy of the PM I just sent to the seller to the same effect.) I swear to the @$&:%@T g*ds, it's always something. And my Haswell has more or less the minimal complement of DIMMs, so pulling a couple of those as a stopgap measure is not an option. Grrr - but it was time for my daily fresh air and exercise walk anyway.

[paulunderwood]

Please send us a piccy when you have mounted the graphics cards.

Is it easy enough to slot in the DIMMs?