Video cards using TurboCache

  • Thread starter Thread starter Peabody
  • Start date Start date
P

Peabody

A while back I got some excellent advice here about upgrading versus
getting a new system (still in the learning phase on that), and one
of the new-system suggestions included a low-end PCI-e video card
using something called TurboCache.

Apparently this involves reducing the ram on the card to something
like 32MB, and using system ram for the rest of the "128MB" of video
ram. Apparently this is made possible by the high-speed
bi-directional transfers available through PCI-e 16x.

But is this just deja vu all over again? Is this just "integrated
video" on a separate card? I thought that the big problem with
integrated video was not so much the use of the ram per se, but
rather the sharing of the memory bus, and the slowdown that
produced. If that's right, how is a Turbocache card better than
something like an integrated ATI Radeon Express 200?

Well, at least it has 32MB on the card. So let me ask this. If no
gaming is involved, is the use of system ram unlikely to happen
often? Would playback of DivX, Xvid, MPEG-2, HD video require the
use of the system ram?
 
A while back I got some excellent advice here about upgrading versus
getting a new system (still in the learning phase on that), and one
of the new-system suggestions included a low-end PCI-e video card
using something called TurboCache.

Apparently this involves reducing the ram on the card to something
like 32MB, and using system ram for the rest of the "128MB" of video
ram. Apparently this is made possible by the high-speed
bi-directional transfers available through PCI-e 16x.

But is this just deja vu all over again? Is this just "integrated
video" on a separate card? I thought that the big problem with
integrated video was not so much the use of the ram per se, but
rather the sharing of the memory bus, and the slowdown that
produced. If that's right, how is a Turbocache card better than
something like an integrated ATI Radeon Express 200?

Well, at least it has 32MB on the card. So let me ask this. If no
gaming is involved, is the use of system ram unlikely to happen
often? Would playback of DivX, Xvid, MPEG-2, HD video require the
use of the system ram?

This is not my area of expertise, so I cannot provide a definitive answer.
However, I do know that older AGP video cards with only 8 megabytes of RAM
will play back DVDs and DivX files with no problems whatsoever. This leads
me to believe that if you are not gaming, you will probably never use
system ram for video.
 
Using a finger dipped in purple ink, Peabody
A while back I got some excellent advice here about upgrading versus
getting a new system (still in the learning phase on that), and one
of the new-system suggestions included a low-end PCI-e video card
using something called TurboCache.

Whoever gave that advice is a moron.
Apparently this involves reducing the ram on the card to something
like 32MB, and using system ram for the rest of the "128MB" of video
ram. Apparently this is made possible by the high-speed
bi-directional transfers available through PCI-e 16x.

Yes, it's called 'shared memory', and it's a cheap way to get a memory
card, AND uses main system memory for video. Not NEARLY as fast as
dedicated video memory.


Lumber Cartel (tinlc) #2063. Spam this account at your own risk.

This sig censored by the Office of Home and Land Insecurity...

Remove XYZ to email me
 
A while back I got some excellent advice here about upgrading versus
getting a new system (still in the learning phase on that), and one
of the new-system suggestions included a low-end PCI-e video card
using something called TurboCache.

I believe I may have been the one that gave you that advise a few
months back, though things have changed somewhat in the past little
bit. If you're looking at a low-cost solution, then an nVidia
TurboCache design isn't a bad card, but now the cost advantage has
mostly evaporated. I'm now seeing regular GeForce 6200 cards selling
for only $10 more than 6200 TurboCache cards. Previously the
difference was most like $60 or $70.
Apparently this involves reducing the ram on the card to something
like 32MB, and using system ram for the rest of the "128MB" of video
ram. Apparently this is made possible by the high-speed
bi-directional transfers available through PCI-e 16x.

Yup, that's about it. The vast majority of the time your video card
is only using a rather small amount of memory (usually less than
16MB), so that can be stored in the on-board memory. When more memory
is needed the video card can swap in and out memory from the main
system memory. Pretty much the same concept as a processor's SRAM
cache, except that we're talking about larger but slower memory here.
But is this just deja vu all over again? Is this just "integrated
video" on a separate card?

Sort of yes, except that with integrated video you tended to use ONLY
main system memory. With TurboCache you're using MOSTLY memory on the
video card and only occasionally going to main memory when needed.
I thought that the big problem with
integrated video was not so much the use of the ram per se, but
rather the sharing of the memory bus, and the slowdown that
produced.

For most applications the "slowdown" is lost in the noise these days,
less than 1%. Where you really take a performance hit is in games,
and there the performance hit can be quite large.

However now that a regular GeForce 6200 costs only about $60-$70 while
the TurboCache ones are running at about $50-$60, the difference in
price is small enough that it's probably worth while spending the few
extra $$$'s for MUCH better 3D performance. In the future 3D
performance is likely to see more use outside of games and high-end
workstation applications, so this $10 is a small investment for the
future.
If that's right, how is a Turbocache card better than
something like an integrated ATI Radeon Express 200?

Well, at least it has 32MB on the card. So let me ask this. If no
gaming is involved, is the use of system ram unlikely to happen
often?

With 2D applications the use of system RAM would be quite rare.
Would playback of DivX, Xvid, MPEG-2, HD video require the
use of the system ram?

Probably not, or at least not often enough to make any difference that
could be measured by a benchmark, let alone any difference that you
would actually *feel*.
 
Tony Hill says...
I believe I may have been the one that gave you that
advise a few months back, though things have changed
somewhat in the past little bit. If you're looking at a
low-cost solution, then an nVidia TurboCache design
isn't a bad card, but now the cost advantage has mostly
evaporated. I'm now seeing regular GeForce 6200 cards
selling for only $10 more than 6200 TurboCache cards.
Previously the difference was most like $60 or $70.

-snip-

Thanks very much for the updated information. I'm looking
at something like an Athlon 64 3500+ system and it looks
like the 6200 series might be a good low-cost match,
particularly with no gaming requirement.
 
Yeah, with regular 2D applications (most Windows apps), pretty much
anything over 8MB or 16MB is unnecessary. Where the huge amounts of
memory on the video card are needed these days are with 3D apps (most
games). The games store their bitmaps onboard the video memory, and the
more video ram there is, the more bitmaps can be stored in there, thus
resulting in greater framerates.

These days, they are starting to even program directly to the GPU using
a method called Pixel Shading. Pixel Shading is a bunch of little
programs that run on the GPU, and they themselves are taking up some of
the space in video memory nowadays too. Again, it's all about games at
the moment. In the future, it might also deal with Windows Vista, as
it's supposed to be using a lot of the functionality of 3D graphics
cards heavily itself, and not just with games running underneath it.

Yousuf Khan
 
Well, at least it has 32MB on the card. So let me ask this. If no
gaming is involved, is the use of system ram unlikely to happen
often? Would playback of DivX, Xvid, MPEG-2, HD video require the
use of the system ram?

no, 32MB is plenty for playback. even decoding hdtv takes only 12MB
 
Back
Top