Personal computing discussed

Moderators: renee, morphine, SecretSquirrel

 
south side sammy
Gerbil
Topic Author
Posts: 67
Joined: Tue Nov 10, 2009 6:48 pm

vram and SSD's

Tue Feb 05, 2013 5:52 pm

scenario........... you have a high res screen.... 1900x1200 for ex.

you run a 2gig video card ( gtx660 for ex. ) the game plays fine there is no faultering.

"pretend" the GTX660 comes in a 1gig version. same game, same settings. card can't handle game for lack of vram and offloads to the HD ( typical 7200rpm drive ). you get spitting and sputtering because of this.

what happens if you replace the HD with an SSD? will the sputtering still happen? will it be less because the data travels faster? will it be the same?
 
XTF
Gerbil
Posts: 59
Joined: Sun Sep 11, 2011 11:55 am

Re: vram and SSD's

Tue Feb 05, 2013 6:21 pm

card can't handle game for lack of vram and offloads to the HD ( typical 7200rpm drive ). you get spitting and sputtering because of this.

Video memory is backed by system memory, not by HDD. So it wouldn't really matter.
 
thecoldanddarkone
Minister of Gerbil Affairs
Posts: 2449
Joined: Wed Mar 26, 2003 4:35 pm

Re: vram and SSD's

Tue Feb 05, 2013 6:47 pm

What he said above and....

The x79 only has a theoretical 52.6 GB/s of bandwidth and my lowly gtx 560 ti has a theoretical 128 GB/s this alone is a huge bottleneck. This gets better though, the pci express 3 spec only supplies 1 GB/s in each direction and even with a 16x slots that's only 16 GB/s each direction.


Bottlenecks, bottlenecks and more bottlenecks.
I7 4930k, 32 GB Ballistix DDRL3@2133 , 1.2 TB Intel 750 AIC, 500 GB mx200, Sapphire R9 Fury, asus x79 ws, HP ZR24w, edifier s730
HP Pro x2 612- i5-4302Y, 8 gigs of memory, 256 ssd
 
south side sammy
Gerbil
Topic Author
Posts: 67
Joined: Tue Nov 10, 2009 6:48 pm

Re: vram and SSD's

Tue Feb 05, 2013 6:52 pm

I guess the question was far above either of yours expertize so I'll wait for somebody that really understands............. that second post has to be meant for some other thread, right? 1st poster, it dumps to the HD.
 
thecoldanddarkone
Minister of Gerbil Affairs
Posts: 2449
Joined: Wed Mar 26, 2003 4:35 pm

Re: vram and SSD's

Tue Feb 05, 2013 7:06 pm

south side sammy wrote:
I guess the question was far above either of yours expertize so I'll wait for somebody that really understands............. that second post has to be meant for some other thread, right? 1st poster, it dumps to the HD.



No, you're misunderstanding what the issue is. Most of the information is pulled off the hard drive during the initial level load, that information gets put into system memory. So the SSD makes a difference here, but most of the transfers beyond that will happen from system memory to the video card. Even if it was pulling from a hard drive the same thing I just said would still apply, but the bottleneck would be even bigger.
I7 4930k, 32 GB Ballistix DDRL3@2133 , 1.2 TB Intel 750 AIC, 500 GB mx200, Sapphire R9 Fury, asus x79 ws, HP ZR24w, edifier s730
HP Pro x2 612- i5-4302Y, 8 gigs of memory, 256 ssd
 
Spyder22446688
Gerbil Jedi
Posts: 1875
Joined: Fri Jul 18, 2003 12:28 pm
Location: Seattle, Washington
Contact:

Re: vram and SSD's

Tue Feb 05, 2013 7:10 pm

south side sammy wrote:
I guess the question was far above either of yours expertize so I'll wait for somebody that really understands............. that second post has to be meant for some other thread, right? 1st poster, it dumps to the HD.


From another forum:

...there is no automatic memory management system built into DirectX for the event that it should run out so how each game handles this is up to whoever wrote the game engine. Some just offload the memory to staged buffers (located in main system memory) - in case of textures (usually the case) the memory/pcie bus speed isnt that bad, just hangs up the cpu a lot because it has to handle all the data transfers so game engines with multiple draw threads handle this much better. More often though the not so relevant data just gets deleted and reloaded when its needed again - this is much simpler to implement but also much slower since now the data has to be brought up in raw form from either the ram(if it was stored there in the first place) or hdd(slooow!).

This is entirely consistent with what I have read on the topic over the years.

In other words, VRAM just keeps re-writing itself or generally offloads to system memory. Assuming for the sake of argument that VRAM was routinely offloaded to the SSD or a HDD (which I dispute), bandwidth and latency problems associated with either a HDD *or* a SSD would be so great that neither would have a meaningful impact on frames-per-second.
x--x--x--x
 
UberGerbil
Grand Admiral Gerbil
Posts: 10368
Joined: Thu Jun 19, 2003 3:11 pm

Re: vram and SSD's

Tue Feb 05, 2013 8:23 pm

As things (texture data, primarily) exceed on-card memory, the video driver swaps with main (system) memory, not with secondary storage (HD, SSD, whatever). The OS memory manager in turn may then start paging out to secondary storage if it is overcommitted (in which case you should be buying more RAM, assuming a 64bit OS, rather than looking for an SSD), but that's outside the purview of the graphics card and its drivers which can't "see" the storage devices and have no idea what SSDs or HDs you might have attached. A game of course may be trying to juggle things between system memory and on-card memory on its own, but I would expect game code that sees constrained video card memory will seek to use less memory overall (ie automatically reduce texture size) to get optimal results. The last thing the game code wants to do is juggle with the disks during gameplay, which is why they try to load as much as they can at the start of a level.

However, to answer your question, let's assume that you are seeing system memory paging due to all of the above (ie insufficient graphics card memory resulting in thrashing through the memory hierarchy to your page file) so that the graphics card is effectively waiting on something getting paged in from the page file or a resource loaded out of the game image*. Pulling a page from the page file is effectively a 4KB random-access read. Latency for that on a recent fast SSD is on the order of 0.03ms, which is fantastic compared to hard drives (which run into several-to-ten or more full ms at best) but that's still extremely slow as far as the GPU and its on-card memory are concerned. Modern GDDR has latencies measured in (single digit) nanoseconds, whereas .03ms is still 3000ns. So loading from SSD might be a hundred times faster than a HD, but it's still a thousand times slower than memory. You might not notice if it's just one 4KB page, but it never is, and if the GPU can't proceed without that data, you're going to see some amount of choppiness.

* Of course getting it off the disk is just the first step; once the data is in memory it has to be DMA'd through to the card. With 16 lanes of PCIe 3.0, the graphics card can pull a full 1GiB of data in 1/16th of a second, and the game probably is waiting on less than that, so (ignoring latency, OS/API overhead, and a host of other things) we'll just ignore any added latency from that stage (it'll be the same for SSD vs HD anyway).
 
maxxcool
Gerbil Elite
Posts: 855
Joined: Thu Sep 12, 2002 8:40 am
Location: %^&*%$$
Contact:

Re: vram and SSD's

Tue Feb 05, 2013 10:23 pm

A ssd will not stop or reduce stuttering at all. Your going from NS access times to MS access times by reaching across multiple system busses by accessing any form of HD. If the engine is bottoming out it is MORE likely your out of user space ...
Cybert said: Capitlization and periods are hard for you, aren't they? I've given over $100 to techforums. I should have you banned for my money.
 
XTF
Gerbil
Posts: 59
Joined: Sun Sep 11, 2011 11:55 am

Re: vram and SSD's

Thu Feb 07, 2013 4:51 am

UberGerbil wrote:
Modern GDDR has latencies measured in (single digit) nanoseconds, whereas .03ms is still 3000ns.

I'd swear 0.03 milliseconds was 30 microseconds, not 3 microseconds.
Data isn't likely to be swapped out from video to system memory, a copy of the data stays in system memory to avoid the cost of swapping out.

south side sammy wrote:
I guess the question was far above either of yours expertize so I'll wait for somebody that really understands............. that second post has to be meant for some other thread, right? 1st poster, it dumps to the HD.

I'm afraid your expertize level is far lower than we expected, sorry for that. ;)
 
Firestarter
Gerbil Elite
Posts: 773
Joined: Sun Apr 25, 2004 11:12 am

Re: vram and SSD's

Thu Feb 07, 2013 5:07 am

An SSD can help for some games to reduce stuttering, but that only happens when the game is not made to take advantage of system RAM (not VRAM) that you may have left, or if you run out of said RAM. This mostly happens with games that stream content instead of loading it all up front, where game engine did not predict that the content was needed and can't display some kind of placeholder (for example lower detail texture/model).

All in all, it should not help in an ideal world where all game engines are perfect, but alas they're not and as such it may help.
 
FubbHead
Grand Gerbil Poohbah
Posts: 3482
Joined: Mon Apr 08, 2002 9:04 pm
Location: Borås, Sweden

Re: vram and SSD's

Thu Feb 07, 2013 6:02 am

Yeah. Open landscape games like, say, Skyrim, that stream content on the fly when you move around in the world, can benefit a lot from SSD. They are usually good at buffering stuff to system memory beforehand, but every now and then there is some content it needs to fetch from disk before it can be presented to you. And then it will choke.

How often this is depends on amount of video memory, system memory, texture quality, view/buffer distance, etc, etc..
Amiga 1200, 68020@28MHz, 4MB+2MB RAM, Conner 80MB harddrive
 
south side sammy
Gerbil
Topic Author
Posts: 67
Joined: Tue Nov 10, 2009 6:48 pm

Re: vram and SSD's

Thu Feb 07, 2013 7:17 am

XTF/ if I already knew the answer I wouldn't have posted the question would I? That's what forums are for. I can see the answers vary from poster to poster to a degree. Thanks for the information. any other opinions ( in relation to the original question ) would still be appreciated. THANK YOU........
 
XTF
Gerbil
Posts: 59
Joined: Sun Sep 11, 2011 11:55 am

Re: vram and SSD's

Thu Feb 07, 2013 7:32 am

south side sammy wrote:
XTF/ if I already knew the answer I wouldn't have posted the question would I?

Probably not, but that's not the point. Don't make statements about the expertize level of people you don't know just because you don't understand their answer.
 
FubbHead
Grand Gerbil Poohbah
Posts: 3482
Joined: Mon Apr 08, 2002 9:04 pm
Location: Borås, Sweden

Re: vram and SSD's

Thu Feb 07, 2013 7:37 am

"pretend" the GTX660 comes in a 1gig version. same game, same settings. card can't handle game for lack of vram and offloads to the HD ( typical 7200rpm drive ). you get spitting and sputtering because of this.


In answer to this question; the stuttering most likely comes from the card having to move data to and from RAM, and not to any drive. No SSD will help you then, but lowering the texture quality and such will. But, if your system is indeed hammering the drive during gameplay, then you are probably low on RAM as well, and the OS starts swapping stuff out from RAM to drive also. Then a SSD will help some. But on the other hand, RAM is much cheaper than a SSD, and will help more..
Amiga 1200, 68020@28MHz, 4MB+2MB RAM, Conner 80MB harddrive
 
just brew it!
Administrator
Posts: 54500
Joined: Tue Aug 20, 2002 10:51 pm
Location: Somewhere, having a beer

Re: vram and SSD's

Thu Feb 07, 2013 7:44 am

FubbHead wrote:
Yeah. Open landscape games like, say, Skyrim, that stream content on the fly when you move around in the world, can benefit a lot from SSD. They are usually good at buffering stuff to system memory beforehand, but every now and then there is some content it needs to fetch from disk before it can be presented to you. And then it will choke.

Yes. But this is separate from the issue presented in the original post. That content probably isn't getting buffered in the VRAM to begin with, so whether SSD vs. HDD helps in this case is going to be independent of the amount of VRAM on the video card.

To the OP:

As others have noted, if you're having issues with insufficient VRAM it is most likely spilling over into system RAM, not the hard drive. This *might* in turn be causing other stuff to get paged out to disk, but the correct solution in this case is to get a card with more VRAM, or (failing that) add system RAM; adding a SSD is going to help very little (if at all) with problems caused by insufficient VRAM.

The SSD may improve your in-game experience in other ways, but these are unrelated to the amount of VRAM you've got.
Nostalgia isn't what it used to be.
 
south side sammy
Gerbil
Topic Author
Posts: 67
Joined: Tue Nov 10, 2009 6:48 pm

Re: vram and SSD's

Thu Feb 07, 2013 8:19 am

actually I don't have any of these problems. it was just a general idea that popped up in my mind and thought I could get some useful information ( opinions ) on the matter. I always assumed the HD got dumped on ( goes back to my early days when either ram supposedly didn't matter for some reason or it was too expensive to buy tons of it or no machine I had could take advantage of more than 3.2gigs.)

nowadays I run high cache processors, twice the memory I think I will ever need and no less than 2gig video cards and 64bit operating systems.

I just thought there might be an advantage, if the case were so, that a low budgeted machine might benefit in some way ( game related to take advantage of it's shortcomings by using a much faster than HD solution. )
 
FubbHead
Grand Gerbil Poohbah
Posts: 3482
Joined: Mon Apr 08, 2002 9:04 pm
Location: Borås, Sweden

Re: vram and SSD's

Thu Feb 07, 2013 8:28 am

Alright. Beside from the fact that a SSD will make almost *any* system this side of 2005 feel much more responsive, there aren't so many benefits game wise aside from perhaps faster loading times. In the scenario when the system is low on RAM and the system starts swapping, you're still better off buying more RAM instead.
Amiga 1200, 68020@28MHz, 4MB+2MB RAM, Conner 80MB harddrive
 
just brew it!
Administrator
Posts: 54500
Joined: Tue Aug 20, 2002 10:51 pm
Location: Somewhere, having a beer

Re: vram and SSD's

Thu Feb 07, 2013 8:42 am

I suppose if the motherboard's RAM is already maxed out and you're still hitting the pagefile, a SSD would help. But that's a contrived situation, and even in that case the SSD is not going to fix any stuttering that results from the paging; it will just turn a massively annoying issue into a somewhat less annoying issue.

Even a fast SSD is still way slower than system RAM, especially in terms of latency. Ditto your system RAM compared to VRAM.
Nostalgia isn't what it used to be.
 
south side sammy
Gerbil
Topic Author
Posts: 67
Joined: Tue Nov 10, 2009 6:48 pm

Re: vram and SSD's

Thu Feb 07, 2013 9:02 am

even a pci-e ssd?
 
just brew it!
Administrator
Posts: 54500
Joined: Tue Aug 20, 2002 10:51 pm
Location: Somewhere, having a beer

Re: vram and SSD's

Thu Feb 07, 2013 10:02 am

south side sammy wrote:
even a pci-e ssd?

Bandwidth of dual-channel DDR3-1866: approximately 30 GB/sec
Bandwidth of a PCIe 2.0 x4 slot: approximately 2 GB/sec (but your hypothetical SSD probably isn't using it all)

Latency of dual-channel DDR-1866: approximately 10 nanoseconds (a bit more once you account for memory controller latency)
Latency of an SSD in a PCIe slot: a few microseconds (possibly up into the 10s of microseconds once you account for OS overhead)

So you're looking at a factor of 15 (or more) difference in bandwidth, and multiple orders of magnitude (like a factor of 100-1000) in latency.

The thing to remember about SSDs is that -- while they are silicon-based -- the OS still talks to them as if they are mechanical hard drives. Which means software has to issue a read or write command to the drive, then wait for an entire sector's worth of data (512 bytes or 4 KB depending on whether the drive uses advanced format) to get moved to/from the drive as a block DMA transfer.

Yes, they're much faster than mechanical drives. But they're also still much slower than RAM!
Nostalgia isn't what it used to be.
 
auxy
Graphmaster Gerbil
Posts: 1300
Joined: Sat Jan 19, 2013 4:25 pm
Location: the armpit of Texas

Re: vram and SSD's

Thu Feb 07, 2013 5:53 pm

just brew it! wrote:
south side sammy wrote:
even a pci-e ssd?

snip
Yes, they're much faster than mechanical drives. But they're also still much slower than RAM!

This really goes a long way to illustrate just how awful mechanical drives are, too, though, for random accesses. It's very interesting how usage pattern affects the performance of a device, as well; mechanical drives are just fine for sequential transfers.

Thought-provoking.
 
just brew it!
Administrator
Posts: 54500
Joined: Tue Aug 20, 2002 10:51 pm
Location: Somewhere, having a beer

Re: vram and SSD's

Thu Feb 07, 2013 6:05 pm

auxy wrote:
just brew it! wrote:
south side sammy wrote:
even a pci-e ssd?

snip
Yes, they're much faster than mechanical drives. But they're also still much slower than RAM!

This really goes a long way to illustrate just how awful mechanical drives are, too, though, for random accesses. It's very interesting how usage pattern affects the performance of a device, as well; mechanical drives are just fine for sequential transfers.

Indeed. Take the latency of an SSD and add a few *more* orders of magnitude and you've got a mechanical HDD. HDDs are suffering relative to SSDs in the sequential transfer department as well, but not by orders of magnitude (yet).
Nostalgia isn't what it used to be.
 
JustAnEngineer
Gerbil God
Posts: 19673
Joined: Sat Jan 26, 2002 7:00 pm
Location: The Heart of Dixie

Re: vram and SSD's

Thu Feb 07, 2013 6:46 pm

Unlike DRAM, the information on your mechanical hard-drive doesn't disappear when you turn the power off.

Unlike SSDs, 3 terabytes of storage on a hard-drive costs $140, instead of $7500.
· R7-5800X, Liquid Freezer II 280, RoG Strix X570-E, 64GiB PC4-28800, Suprim Liquid RTX4090, 2TB SX8200Pro +4TB S860 +NAS, Define 7 Compact, Super Flower SF-1000F14TP, S3220DGF +32UD99, FC900R OE, DeathAdder2
 
auxy
Graphmaster Gerbil
Posts: 1300
Joined: Sat Jan 19, 2013 4:25 pm
Location: the armpit of Texas

Re: vram and SSD's

Thu Feb 07, 2013 7:19 pm

JustAnEngineer wrote:
Unlike SSDs, 3 terabytes of storage on a hard-drive costs $140, instead of $7500.

($7500? I figure ~$2400 at current market prices. Although the point still stands.)
Yeah, that's true, but, you know ...

I used to be like a lot of people and try to archive everything. You know, watch this anime series and think "gosh, that was really good; I should hold onto it forever so I can share it with my friends!", or download and save every picture I like on every imageboard and image host, so I can repost it later at just the right moment, or download entire discographies of bands who have one song I like, so I can listen to it later.

And then I realized that I NEVER do this. Any of it.

Really, these days, I think a lot of people buy into the mindset of "duuuude, 2 terabytes", when they hardly even use the disk space they have. A 120GB SSD is more than sufficient for most people; my personal system has a 128GB system drive, four 60GB SSDs, and a 16GB SATA RAMdisk, and I scarcely use more than 40GB of any of the drives*. And I'm a very active gamer!

tl;dr The point being that I really think the actual *value* of having terabytes of storage laying around is vastly overstated for *most* people.

*(I do have 4TB of storage hooked up to my HTPC, but it's barely half-full, and much of that is music that I've simply kept around and much of that I've never even listened to.)
 
JustAnEngineer
Gerbil God
Posts: 19673
Joined: Sat Jan 26, 2002 7:00 pm
Location: The Heart of Dixie

Re: vram and SSD's

Fri Feb 08, 2013 12:07 am

I find that my photography can use large amounts of storage space. Some of those photos could never be re-taken, so I've got backups, of course.

Look up the price for a 1 TB SSD.
· R7-5800X, Liquid Freezer II 280, RoG Strix X570-E, 64GiB PC4-28800, Suprim Liquid RTX4090, 2TB SX8200Pro +4TB S860 +NAS, Define 7 Compact, Super Flower SF-1000F14TP, S3220DGF +32UD99, FC900R OE, DeathAdder2
 
auxy
Graphmaster Gerbil
Posts: 1300
Joined: Sat Jan 19, 2013 4:25 pm
Location: the armpit of Texas

Re: vram and SSD's

Fri Feb 08, 2013 5:15 pm

JustAnEngineer wrote:
I find that my photography can use large amounts of storage space. Some of those photos could never be re-taken, so I've got backups, of course.
Of course, of course. I never said that *nobody* could use the space, after all. :)
JustAnEngineer wrote:
Look up the price for a 1 TB SSD.
Isn't that a bit silly? Wouldn't it be much more cost-efficient to buy several smaller disks? I was basing my estimate on the idea of buying 6 512GB drives (around $420 apiece), which makes a bit more sense to me.
 
JustAnEngineer
Gerbil God
Posts: 19673
Joined: Sat Jan 26, 2002 7:00 pm
Location: The Heart of Dixie

Re: vram and SSD's

Fri Feb 08, 2013 9:29 pm

It would make the most sense to buy a single 3 TB SSD to compare to the $140 3 TB hard-drive, but Newegg doesn't offer an SSD that large. They do have a 1 TB SSD for $2500.
· R7-5800X, Liquid Freezer II 280, RoG Strix X570-E, 64GiB PC4-28800, Suprim Liquid RTX4090, 2TB SX8200Pro +4TB S860 +NAS, Define 7 Compact, Super Flower SF-1000F14TP, S3220DGF +32UD99, FC900R OE, DeathAdder2
 
auxy
Graphmaster Gerbil
Posts: 1300
Joined: Sat Jan 19, 2013 4:25 pm
Location: the armpit of Texas

Re: vram and SSD's

Fri Feb 08, 2013 9:41 pm

Yah, I see what you're sayin'. I still think it's silly, though. ¦3c
 
jihadjoe
Gerbil Elite
Posts: 835
Joined: Mon Dec 06, 2010 11:34 am

Re: vram and SSD's

Sat Feb 09, 2013 5:09 am

auxy wrote:
I used to be like a lot of people and try to archive everything. You know, watch this anime series and think "gosh, that was really good; I should hold onto it forever so I can share it with my friends!", or download and save every picture I like on every imageboard and image host, so I can repost it later at just the right moment, or download entire discographies of bands who have one song I like, so I can listen to it later.

And then I realized that I NEVER do this. Any of it.


A few years ago I stopped archiving everything, and then regretted it when I decided I'd like to watch some early-mid 2000s tv shows and anime. Unlicensed stuff from that time can be very hard to find now, and even if you do spot a torrent more often than not there are no more seeds and/or the trackers are dead. Even licensed stuff eventually goes out of print. Want to see the Ranma 1/2 TV series today? I tried browsing the Viz website (they had the license to this in the 90s) and they don't even have DVDs for it anymore.

Disk space is cheap, I've since gone back to archiving everything I like.
 
auxy
Graphmaster Gerbil
Posts: 1300
Joined: Sat Jan 19, 2013 4:25 pm
Location: the armpit of Texas

Re: vram and SSD's

Sat Feb 09, 2013 3:53 pm

jihadjoe wrote:
A few years ago I stopped archiving everything, and then regretted it when I decided I'd like to watch some early-mid 2000s tv shows and anime. Unlicensed stuff from that time can be very hard to find now, and even if you do spot a torrent more often than not there are no more seeds and/or the trackers are dead. Even licensed stuff eventually goes out of print. Want to see the Ranma 1/2 TV series today? I tried browsing the Viz website (they had the license to this in the 90s) and they don't even have DVDs for it anymore.

Disk space is cheap, I've since gone back to archiving everything I like.
Well, maybe I'm applying my own personal opinion too broadly. Still, I do computer consulting work from my home and most of my customers' computers with 240-1000GB HDDs have more than half their space left; most of the 1TB drives are using less than 200GB. So, this view isn't formed merely from my own personal experience.

I appreciate that you guys like to archive things, but I still think most people are better-served with an SSD.

Who is online

Users browsing this forum: No registered users and 1 guest
GZIP: On