Opteron dual vs 2 single opteron

willisub wrote on 3/10/2006, 1:19 PM
I just ran a bunch of render test from Vegas 6 on a Single Opteron 250 (2.4 GHz) with 1 gig ram.
I then ran most of same tests with 2 Opteron 250's and 1 gig for each cpu.
I then added 1 more gb for ram to each of the 2 opteron 250's for 2 GB each.

The extra ram didn't do much.
The upside on the second processor was dependent on the codec used for the render.

Basically, windows media HD 8 and 10 MB per second went from 20 minutes down to 11. MPeg 2 was faster by around 2;52 DOWN TO 1:39 FOR HD.

Comments

willisub wrote on 3/10/2006, 1:23 PM
Sorry, hit the wrong key , continuing
QT was a little faster, but didn't use the 2nd processor.

Did same tests on Dual Xeon 2.4 w/ 2 GB ram. Single opteron 2.4 was faster most of the time, but not alot.

My question, does any one have any experience on using one dual core Opteron as opposed to the 2 Single Core Opteron's.?

I hope this split post doesn't cause too many problems. Again, Sorry for the mess.

Wes C. Attle wrote on 3/11/2006, 6:53 AM
In most benchmarks a dual-core CPU is just as fast as two single-core CPU's of the same speed. The only difference comes when the single-core CPU's have more L2 cache. That difference is tiny though and only in very high-end benchmarks.

Since Opteron's have the same L2 cache size on dual and single core CPU's, they will perform exactly the same in all benchmarks. So two Opteron 252's perform just as fast as one Opteron 285, or one Opteron 185, or one Athlon FX60 in all benchmarks.

As for Intel... these are dark times for them. Can't keep up with AMD. But rumors are they will recover with a new architecture by 2007.
JohnnyRoy wrote on 3/11/2006, 10:16 AM
> As for Intel... these are dark times for them. Can't keep up with AMD. But rumors are they will recover with a new architecture by 2007.

Yea, I feel real bad for Apple. It seems they have jumped onto the loosing horse. (On second thought... No I don’t!. Now it’s undisputable that PC’s are better than Macs)

Maybe the new Apple logo should be, “Unfortunately, Only Intel Inside” ;-) UOII

~jr
Coursedesign wrote on 3/11/2006, 10:22 AM
Since Opteron's have the same L2 cache size on dual and single core CPU's, they will perform exactly the same in all benchmarks. So two Opteron 252's perform just as fast as one Opteron 285, or one Opteron 185, or one Athlon FX60 in all benchmarks.

Sorry, that is not correct in many cases.

The difference is in how effectively the cores can communicate with each other, compared to how two discrete CPUs communicate on a dual processor mobo.

I have seen recent benchmarks for pro apps showing a very significant difference, don't have time to pull them right now, but can do later if desired.

Wes C. Attle wrote on 3/11/2006, 9:14 PM
Coursedesign, I would like to see those benchmarks. I suppose NUMA can make a small difference in some cases.

I've been testing myself with a TYAN K8WE with two Opteron 252's (with NUMA) and a single Athlon 64 X2 4400 on a very low end motherboard. The benchmarks are always about 16% different, that's equal to the 400 MHz difference in CPU speed. Certainly everything in Vegas, Lightwave 3D, and Hash Animation Master is on par. I ignore all synthetic benchmarks since real world benchmarks dictate the performance truth.

I was pretty psyched to get NUMA working when I first got the board. But I quickly found out that NUMA will not do much until you have four physical processors in a system. Two is just not enough to take advantage of NUMA.

willisub wrote on 3/12/2006, 5:44 PM
PetterRabby says

"
I've been testing myself with a TYAN K8WE with two Opteron 252's (with NUMA) and a single Athlon 64 X2 4400 on a very low end motherboard. The benchmarks are always about 16% different, that's equal to the 400 MHz difference in CPU speed. Certainly everything in Vegas, Lightwave 3D, and Hash Animation Master is on par."

so.................................

If I read you right, theb the 64 X2 4400 is at 2.2 Mhz is 16% slower than the 2 Opterons 252's making your statement about two processsors at the same speed are the same as a duo core at the same megahertz.

So if I don't need the pci-x slots that I'm using on the Opteron system, one will get the same performance from the Athlon 64 system which can be built for a lot less. Am I over simplifying this?

I don't suppose Vegas and our other graphic programs benefit from the registered ECC memory over what the Athlon's non ECC memory (which is a lot less expensive.).

Sorry for my ignorance, butwhatis NUMA?
Wes C. Attle wrote on 3/13/2006, 7:14 AM
Yes, you will get the same ballpark of performance from a single dual-core Athlon 64 X2 system as you would from a dual single-core Opteron system running processors at the same speed (in all things Vegas related and everything else I have tested). And the Athlon X2 system can cost you about 1/4 the price of the Opteron system because the motherboard is much cheaper, the CPU is WAY cheaper, non-ECC/Reg memory is cheaper as you said.

When X2 processors released I built the X2 system for my wife for $1200 after I built the Opteron system for myself for much more $$ than I will ever admit (to my wife :). I was shocked that performance is the same across the board relative to CPU speed. Dual-core CPU's can and should replace the single-core dual CPU market.

The advantage of Opteron is you can get two dual-core CPUs on one system, for a bundle of money. The four cores will roughly cut in half your MPEG2 and AVI encoding and render times, depending on what effects and 3rd party filters you apply to the media. (Some effects like Magic Bullet and many other can reduce CPU utilization to one CPU. Four-cores will also improve your WMV encoding by about 20 to 30% over two-cores. But most consumer software still can only utilize a single core.

The newest X2 boards have PCI-ex slots that do fine in place of PCI-X. The performance experience for all things video is much improved simply by adding disks in RAID. So you could get a $100 X2 motherboard with 4 SATA ports and onboard nvRAID. Put two small disks in RAID 1 for your Windows & Program files. Two more larger disks in RAID 0 for your media files and project work. (Hint: put your Windows swap file on the RAID 0/media disk and Vegas encoding performance jumps 10% or more.) Or you could add a PCI-ex RAID card and have more disks. Lot's of disks is great for video no matter what. Just avoid RAID 5 because of slow write performance. RAID 0 or 10 are best for your media drives. Raid 1 system drives are wise for data protection, especially with all the new DRM and serial # registrations that make it a major headache every time you have to reformat and reinstall windows these days.

NUMA is just AMD's Opteron enhanced memory management to route traffic to the memory controller that has the shortest backlog of requests. But it can add latency and doesn't change my benchmarks much on a two proc system. NUMA does a good job for 4 to 8 proc SQL servers with millions of user's traffic (my day job), but not for most common prosumer two processor workstation environments.

Anyway, my point is that I have both an Opteron workstation which I enjoy greatly and an X2 system. I recommend X2 all the way simply for much lower price with the same overall performance. Get at least 2 GB RAM. Helps for Vegas and multi-tasking with media. Not to mention you will be on 64-bit Windows Vista by next year.

But if you render AVI or encode MPEG for dozens of hours every week, then all the time saved with a double dual-core Opteron system might be worth it.

ECC memory can improve OS/system stability in certain situations, but actually hurts performance a tiny tiny bit.

PS - AMD will release new Athlon and Opteron sockets this summer with DDR2 memory support. The current socket 939 and 940 will be phased out at the end of this year. But don't worry, the current platform is very matured, stable, and well-priced right now. A new system bought today will be good for a few years. The next generation DDR2 design will only bring about 10% performance gain until the much faster processors and quad-core Opterons come out in early 2007.

Also, right now is a very bad time to buy a new high-end graphics card if you plan to upgrade to Windows Vista. nVidia will release their G80 cards by the end of summer/Fall with DirectX 10 and Shader Model 4.0 hardware support. All the video cards on sale at this moment will not support Vista's DirectX 10 or SM 4.0, so they will be somewhat obsolete when those new technologies become main stream in games and graphics applications in 2007. So I wouldn't spend too much on a new card until later this year.

Sorry for the long post!