980X HT Off & 3 Physical cores @ 5Ghz Possible?

[audiohavoc 24]

FSX runs on a single core. All the cores do is load scenery.For FSX to be truly multi-core, ACES would have had to completely re-write the FSX engine.They were supposed to do this for FSXI, together with multi-GPU. Sigh.Cheers,- jahman.

Yes, but reducing the amount of cores and forcing the terrain/scenery threads to work on the same cores as the OS, FSX apps, and the primary FSX code seems to me that this would increase the chance of thread collisions, and would lead to stuttering. Having more cores allows for more efficient thread management.

[Bob Scott 7,725]

First, I don't know if any of the current mobos will allow you to disable 3 cores in the BIOS. I have an i7-975, and my options are four, two, or single core operation. My gut feel is a 980 would be allowed 1/2/4/6 core ops, but I'm only guessing.My theory, which seems to bear some fruit in practice, is that shutting down some of the cores on the chip reduces heat and allows the remaining cores to be clocked a notch or two higher. That's particularly interesting on the 980X, because FSX doesn't really make good use of six cores, and much of the benefit of a 32nm CPU (lower power, lower heat, and higher O/C limit as a result) is lost as a result of adding back in two more cores and the supporting circuitry associated with them. Most of the folks I've chatted with that have clocked a 980 are not getting significantly higher clocks than the 975 if they run all six cores.I shut down two cores on my 975, and with the same voltage settings that I used for my previous best overclock (4.55 GHz with Vcc at 1.49v) I was able to get the 975 to 4.7 GHz with an aggressive water cooling system. This is a tremendous performer in FS9, which only uses one core...not so much in FSX since having an extra core at 4.55GHz adds more than having two thirds the cores but running 3% faster.I use affinity mask=12 right now in FSX...it seems smoother to me, where AM=14 produced a frame or two higher and marginally better AG fills, but with the occasional teeny tiny microstutter. I'm thinking that's due to less than perfect timing between the paralleled threads. So if a 980 could be run on 3 cores via BIOS with AM=12 and overclocked to near 5 GHz, that'd be a very interesting development...maybe the fastest configuration possible on current hardware short of very expensive/exotic phase change coolers and a need to run voltages beyond Intel's absolute max specs for the chip.CheersBob ScottColonel, USAF (ret)ATP IMEL Gulfstream II-III-IV-VColorado Springs, CO

[acmech 2]

Good to hear from you BOB!I tested my system with only one core enabled. Fs9 ran about the same as 2 cores enabled.Then I went ahead and ran three cores @4.88 ghz . Fs9 even responded better then with 2 cores. I could not go higher then 4.88 ghz on air cooling.At 5.0 ghz system started and a short time in the sim it went too blue screen.So 4.88 ghz has been very stable with 3 cores running.Temp differance between 2 cores and three cores enbled is about 2*c .My SpecsIntel Core i7-980X Extreme Edition Gulftown 3.33GHz 6 x 256KB L2 Cache 12MB L3 Cache LGA 1366 130W overclocked @4.88GHz vcore 1.23stock CPU Cooler ASRock X58 Extreme LGA 1366 Intel X58 ATX Intel Motherboard bios 2.60G.SKILL Trident 6GB (3 x 2GB) 240-Pin DDR3 SDRAM DDR3 2000 (PC3 16000) Triple Channel Intel X25-M Mainstream SSDSA2M160G2XXX 2.5" 160GB SATA II MLC Internal Solid State Drive (SSD) For fs9 and OSIntel X25-V SSDSA2MP040G2R5 2.5" 40GB SATA II MLC Internal Solid State Drive (SSD) for other stuffEVGA 02G-P3-1185-AR GeForce GTX 285 2GB 512-bit DDR3 PCI Express 2.0 x16 Creative - Sound Blaster X-Fi XtremeGamer Sound CardOCZ 750W SLI/CrossFire Active PFC Power Supply Acer GD235HZbid Black/orange 23.6" 2ms Widescreen 1080p 120Hz 3D-Ready LCD Monitor

[Bob Scott 7,725]

Good to hear from you BOB!I tested my system with only one core enabled. Fs9 ran about the same as 2 cores enabled.Then I went ahead and ran three cores @4.88 ghz . Fs9 even responded better then with 2 cores. I could not go higher then 4.88 ghz on air cooling.At 5.0 ghz system started and a short time in the sim it went too blue screen.So 4.88 ghz has been very stable with 3 cores running.Temp differance between 2 cores and three cores enbled is about 2*c .

OK, then that answers my question about whether there's BIOS support for 3-core operation.You really need to get a 480 into that machine!CheersBob ScottColonel, USAF (ret)ATP IMEL Gulfstream II-III-IV-VColorado Springs, CO

[acmech 2]

OK, then that answers my question about whether there's BIOS support for 3-core operation.You really need to get a 480 into that machine!CheersBob ScottColonel, USAF (ret)ATP IMEL Gulfstream II-III-IV-VColorado Springs, CO

I use to have the ati 4870 2gb card and it never had issues with gagged edges in windowed mode. Although ,that card was two gpu's which acted like crossfire,so in return frames were lower. So if I choose a single gpu card by ATI, that is very powerful (ATI 5870 2gb) I could have best of both worlds again...Whats your thought on that card? I always seem to have issues with nvidia cards. Which ,I have owned many of those bad boys.

[Bob Scott 7,725]

I use to have the ati 4870 2gb card and it never had issues with gagged edges in windowed mode. Although ,that card was two gpu's which acted like crossfire,so in return frames were lower. So if I choose a single gpu card by ATI, that is very powerful (ATI 5870 2gb) I could have best of both worlds again...Whats your thought on that card? I always seem to have issues with nvidia cards. Which ,I have owned many of those bad boys.

I have a 5870 as a backup for my 480...it's a solid card, will hold mid 20s for frame rates with 2XAA supersampling, which is acceptable for FSX performance. Not sure what benefit a 2GB card would be, though. CheersBob ScottColonel, USAF (ret)ATP IMEL Gulfstream II-III-IV-VColorado Springs, CO

[Guest jahman]

(snip)... Not sure what benefit a 2GB card would be, though. CheersBob ScottColonel, USAF (ret)ATP IMEL Gulfstream II-III-IV-VColorado Springs, CO

A 2 GBy video card could actually even be counterproductive!As a 32-bit app, FSX can only address 4 GBy max, so the RAM available to FSX is 4 GBy minus VRAM minus RAM used by Windows and other apps. If you increase VRAM from 1 GBy to 2 GBy you are automatically reducing the amount of RAM that can be used by FSX by 1 GBy!If running Win-64, you have slightly more RAM available to FSX as the size of the 32-bit compatibility box of Win-32 under Win-64 would be, I presume, smaller than full-blown Win 32. (Can anybody confirm this?)When running FSX under DX10 VRAM is virtualized (i.e. every program thinks it has exclusive use of VRAM and the GPU, when in reality VRAM and GPU are shared) so the situation is again different, but "nobody in the know" (knowbody! :-) has yet been able to explain to me how virtualized VRAM affects FSX RAM usage.Cheers,- jahman.

[acmech 2]

Well, I will find out soon .I ordered a POWERCOLOR AX5870 2GBD5-M6D Radeon HD 5870 (Cypress XT) 2GB 256-bit GDDR5. Ati is in my opinion smoother in graphics from all the cards I have owned. Like everything in life it all up to what makes you happy. I am hopping for the best. One other reason I have went with ati is because of FShot seat .It runs then as it adjusts to full screen mode for some reason it makes nvidia cards view as in windowed mode.

[Bob Scott 7,725]

As a 32-bit app, FSX can only address 4 GBy max, so the RAM available to FSX is 4 GBy minus VRAM minus RAM used by Windows and other apps. If you increase VRAM from 1 GBy to 2 GBy you are automatically reducing the amount of RAM that can be used by FSX by 1 GBy!

No, the VRAM in Vista and W7 in WDDM 1.1 and later are both virtualized, and only allocated as needed by the app, so the entire VRAM address space is NOT duplicated in the user's address space like it was in XP and pre-SP1 versions of Vista. In a 64-bit environment, RAM used by Windows is virtualized above the 4GB boundary, so it does not come out of the app's available 4GB of virtual address space. And other applications each have their own 4GB virtual address spaces to work with independent of the others.

If running Win-64, you have slightly more RAM available to FSX as the size of the 32-bit compatibility box of Win-32 under Win-64 would be, I presume, smaller than full-blown Win 32. (Can anybody confirm this?)

When running Win 64 you have much more than "slightly" more RAM available...the entire 4GB 32-bit address space is available to FSX, as opposed to an absolute max of 3GB in Win 32--and that only if you can make Windows behave in 1GB with the /3GB switch.

When running FSX under DX10 VRAM is virtualized (i.e. every program thinks it has exclusive use of VRAM and the GPU, when in reality VRAM and GPU are shared) so the situation is again different, but "nobody in the know" (knowbody! :-) has yet been able to explain to me how virtualized VRAM affects FSX RAM usage.

It's not just under DX10...VRAM virtualization is a function of WDDM versions used by both Vista SP1+ and W7. The important piece of this for FS is that Windows does not just automatically allocate a block of shared graphics memory equal to size of the entire hardware graphics memory array. It instead, allocates only what is actually used by the application. This is much less than the 2GB present in subject 285GTX card...generally we're talking about 300-400MB. That number doesn't change with the size of the video card.What does typically slow down the 2GB cards is the memory clock speed...all of the 2GB cards I've looked at had their memory clocked considerably (5-10%) slower than the 1GB or less versions of the same card, presumably due to the higher latency introduced by adding another bank of RAM ICs. For FS, that extra gig of VRAM is not used except for very aggressive AA settings at very high screen resolutions, both of which can seriously detract from frame rates. For DX10/11 games, it might be useful.RegardsBob ScottColonel, USAF (ret)ATP IMEL Gulfstream II-III-IV-VColorado Springs, CO

[Guest jahman]

No, the VRAM in Vista and W7 in WDDM 1.1 and later are both virtualized, and only allocated as needed by the app, so the entire VRAM address space is NOT duplicated in the user's address space like it was in XP and pre-SP1 versions of Vista. In a 64-bit environment, RAM used by Windows is virtualized above the 4GB boundary, so it does not come out of the app's available 4GB of virtual address space. And other applications each have their own 4GB virtual address spaces to work with independent of the others.

The VRAM FSX uses (virtualized or not) needs to come out of its 4GBy address space. Any RAM or VRAM beyond 4 GBy cannot be used by FSX. What needs to be explained is if FSX is presented with 2 GBy VRAM, will FSX use the entire 2 GBy? If not, how does FSX determine how much VRAM to use?

When running Win 64 you have much more than "slightly" more RAM available...the entire 4GB 32-bit address space is available to FSX, as opposed to an absolute max of 3GB in Win 32--and that only if you can make Windows behave in 1GB with the /3GB switch.

That is not true. With the 32-bit versions of Windows, all of the OS sits inside the 4 GBy. With 64-bit Windows running a 32-bit app like FSX, only the 32-bit compatibility data structures sit inside the 4 GBy. But they do exist, and they take-up space. Note that if the Win-32 compatibility box had a zero RAM footprint, then FSX could not communicate with the operating system. The question remains: How much space? (Possibly dependent on the scope of services requested from the OS by the app.)

It's not just under DX10...VRAM virtualization is a function of WDDM versions used by both Vista SP1+ and W7. The important piece of this for FS is that Windows does not just automatically allocate a block of shared graphics memory equal to size of the entire hardware graphics memory array. It instead, allocates only what is actually used by the application. This is much less than the 2GB present in subject 285GTX card...generally we're talking about 300-400MB. That number doesn't change with the size of the video card.

That is an interesting piece of information and a powerful reason not to use DX9, especially with video cards sporting 1 GBy VRAM and above. Can you confirm then that any VRAM over 400 MBy goes unused by FSX?

What does typically slow down the 2GB cards is the memory clock speed...all of the 2GB cards I've looked at had their memory clocked considerably (5-10%) slower than the 1GB or less versions of the same card, presumably due to the higher latency introduced by adding another bank of RAM ICs. For FS, that extra gig of VRAM is not used except for very aggressive AA settings at very high screen resolutions, both of which can seriously detract from frame rates. For DX10/11 games, it might be useful.

I apologize for belaboring the point, but now you are saying under certain AA settings and high screen resolutions FSX could use more than 1 GBy of VRAM so I am confused. Can you explain further?Cheers,- jahman.

[Bob Scott 7,725]

The VRAM FSX uses (virtualized or not) needs to come out of its 4GBy address space. Any RAM or VRAM beyond 4 GBy cannot be used by FSX. What needs to be explained is if FSX is presented with 2 GBy VRAM, will FSX use the entire 2 GBy? If not, how does FSX determine how much VRAM to use?

You're confusing VRAM (the actual physical memory on the video card) with the shared graphics buffer created in the user address space. The amount of memory allocated is the size of the vertex buffers used by FSX, which by practical measurement is ~300-400MB.

That is not true. With the 32-bit versions of Windows, all of the OS sits inside the 4 GBy. With 64-bit Windows running a 32-bit app like FSX, only the 32-bit compatibility data structures sit inside the 4 GBy. But they do exist, and they take-up space. Note that if the Win-32 compatibility box had a zero RAM footprint, then FSX could not communicate with the operating system. The question remains: How much space? (Possibly dependent on the scope of services requested from the OS by the app.)

It's a trivial amount of space compared to having an address space the size of the entire usable video memory array blocked due to hardware mapping. In the 32-bit environment, by the time the OS loads, the BIOS has already blocked out a block of addresses that will be used to address the VRAM array (and some other hardware address mappings as well). As to the question of how much space the 32-bit compatibility data structures (i.e. mapped 32-bit addresses for kernel procedure calls)...not sure. What I am sure of, though, is a very significant increase in application address space headroom in a 64-bit environment.

That is an interesting piece of information and a powerful reason not to use DX9, especially with video cards sporting 1 GBy VRAM and above. Can you confirm then that any VRAM over 400 MBy goes unused by FSX?

I don't follow your logic here...WDDM only allocates the video address space actually used by the application in BOTH DX9 and DX10. The difference is between XP and Vista/W7, not DX9 and DX10.

I apologize for belaboring the point, but now you are saying under certain AA settings and high screen resolutions FSX could use more than 1 GBy of VRAM so I am confused. Can you explain further?

No, I am saying that under those settings the VRAM is used--not directly by FSX, but by D3D, the driver, and the card's firmware, which are doing a tremendous amount of processing behind the scenes. AA and AF are done at the firmware/hardware level, not by the application (FS in this case). The AA/AF processes use a sizeable block of VRAM themselves, especially at high AA/AF settings.RegardsBob ScottColonel, USAF (ret)ATP IMEL Gulfstream II-III-IV-VColorado Springs, CO

[bojote 20]

I am using fs9 with my system overclocked @4.88 ghz temp @ 46* c with stock heat sink/fan vcore 1.23v and all but 2 cores running (shut down all but 2 cores in bios) ( hyper threading off).Fs9 responded, awsome in each and every condition .So far with these settings I have seen my sim run the best I have ever seen ! It responds much better (heat/preformance) then when I had all 6 cores running! When I had hyper threading on system slows down in the sim.

Exactly the info I was looking for ;)Thank you VERY much!

FSX runs on a single core. All the cores do is load scenery.For FSX to be truly multi-core, ACES would have had to completely re-write the FSX engine.They were supposed to do this for FSXI, together with multi-GPU. Sigh.Cheers,- jahman.

100% correct. Thats precisely why I started this thread. FSX won't benefit from having MORE cores, but MORE Ghz due to how is programmed.

My theory, which seems to bear some fruit in practice, is that shutting down some of the cores on the chip reduces heat and allows the

Bob, your theory is not only right, but used recently by nVidia when they DISABLED cores in their 480's to increase processor yields ;)

[bojote 20]

I use affinity mask=12 right now in FSX...it seems smoother to me, where AM=14 produced a frame or two higher and marginally better AG fills, but with the occasional teeny tiny microstutter. I'm thinking that's due to less than perfect timing between the paralleled threads. So if a 980 could be run on 3 cores via BIOS with AM=12 and overclocked to near 5 GHz, that'd be a very interesting development...maybe the fastest configuration possible on current hardware short of very expensive/exotic phase change coolers and a need to run voltages beyond Intel's absolute max specs for the chip.

same here :) AM=12 provides MUCH more smoothness and less stutters, due to, fiber/thread interaction being simpler (fibers cooperatively multitask and need to be in perfect armony with the threads) the more threads, more possibility for problems. So, in my opinion a 980x + 3 Cores @ 5Ghz (if possible) is the perfect config for FSX.

[Bob Scott 7,725]

same here :) AM=12 provides MUCH more smoothness and less stutters, due to, fiber/thread interaction being simpler (fibers cooperatively multitask and need to be in perfect armony with the threads) the more threads, more possibility for problems. So, in my opinion a 980x + 3 Cores @ 5Ghz (if possible) is the perfect config for FSX.

It does make a guy wonder what will be possible when all the variations of intel's 32nm quads are on the street.CheersBob ScottColonel, USAF (ret)ATP IMEL Gulfstream II-III-IV-VColorado Springs, CO

[TechguyMaxC 516]

It does make a guy wonder what will be possible when all the variations of intel's 32nm quads are on the street.CheersBob ScottColonel, USAF (ret)ATP IMEL Gulfstream II-III-IV-VColorado Springs, CO

Sadly, Intel will not be releasing quad-core derivatives of the Westmere family of microprocessors. It's dual and hexa-core only until the Sandy Bridge family hits next year, when there will again be quad, hex, and perhaps even octa-core variants. Sandy Bridge is also a new architecture, not a refresh of Nehalem as is Westmere.