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jtrwallace · Jun 14, 2007, 03:24 PM

Ok, I posted this on AI Forums as well but I was wondering if maybe someone here had some more information on this issue. On bootcamp, my new 2.4 MBP says that my video card has 512 mb of VRAM and on OS X it says that I have 256 mb of VRAM. Does this mean that the video card has better capabilities under Windows that it does not have under OS X? Also, can someone else check this out? Confused here.

mduell · Jun 14, 2007, 04:09 PM

May just be a confused driver, since the 8600GT supports 512MB RAM, but Apple only installs 256MB.

Brentnal · Jun 15, 2007, 01:48 AM

Could be related to the "TurboCache" feature that NVIDIA cards have. I don't believe OS-X takes advantage of this technology.

Read TurboCache - Wikipedia, the free encyclopedia

buddy1065 · Jun 15, 2007, 07:55 AM

I thought I read somewhere Vista makes use of the turbocache.

mduell · Jun 16, 2007, 04:04 PM

I don't think any of the 8-series mobile GPUs support TurboCache.

yoyoman · Jun 17, 2007, 04:46 PM

512? serious?

buddy1065 · Jun 17, 2007, 05:22 PM

Well for whatever reason the 2.4 Ghz got twice as many FPS over my 2.33 MBP with 256 ATI. I ran my Oblivion character across the long bridge near Chestnut Handy stables at 1280x768 on both laptops; the 2.4 Ghz I bought yesterday gave me 52 to 56 FPS while the 2.33 Ghz only gave 21 to 22 FPS. This was only one test however and I will be making more. For now it looks like I am the only one fortunate enough to perform real world FPS tests on both laptops. Don't have the 2.2 Ghz though sorry!

http://i117.photobucket.com/albums/o...leyT99/FPS.jpg

Oh yeah, I am using XP Home. For now I'm staying away from Vista; too many complaints.

cambro · Jun 17, 2007, 05:31 PM

It doesn't matter either way.

Tests have shown that the 128-256MB difference in VRAM translates into ZERO performance difference in graphic intensive games.

Unless you are going to use your MBP to push multiple 30" displays, you have some specialized app that uses the GPU more heavily than the latest games do, or you just like to say "I have 512 MB" then it doesn't matter....though the observation is interesting in a gee-whiz sort of way.

jtrwallace · Jun 18, 2007, 05:07 PM

hmm, interesting. i suppose it wont matter much but like you said its nice to say "i have 512 MB" when you didnt even ask for it

smitty825 · Jun 19, 2007, 12:08 AM

Hmmm...maybe I'm stupid (and it wouldn't be the first time...), but I don't see how the MBPs can run multiple 30" displays. There is one DVI out port, no separate VGA port, and no other way to get video out. If you want a second 30" display, you'd need an express card based video card, which would have its own separate video memory, correct?

giggs11 · Jun 19, 2007, 04:42 PM

One thing I haven't seen mentioned when it comes to the VRAM question is the introduction of Core Animation in Leopard. I just feel like over time, developers will take more advantage of its capabilities and leave those of us with less capable video cards behind.

buddy1065 · Jun 19, 2007, 07:05 PM

Cambro, I still have my doubts there is such a small FPS difference in XP, since Barefeats tests in OSX. Even they find it interesting in the huge FPS difference as I quote them here,

"PC GAMING vs Mac GAMING
We installed a copy of Prey under both Mac OS X and Windows XP Pro. In our first test, we ran at 960x600 in windowed mode, max quality settings, 4X FSAA, 4X anisotropic filtering. Under Mac OS, the 17" MacBook Pro 2.4GHz scored 37fps. Under Windows XP Pro, it scored 73fps. Hmmm."

Xp FPS may well be a whole different ball game.

buddy1065 · Jun 19, 2007, 07:20 PM

I found this post interesting from here
MacBook Pro Santa Rosa 128MB vs 256MB - Benchmark compilation - Page 2 - Notebook Forums and Laptop Discussion

Quote:
More "VRAM Wars" -- 15" MacBook Pro 2.2GHz (128M VRAM) versus 2.4GHz (256M VRAM).

Under Windows XP Pro, I ran 3DMark06 at 1440x900, 4X FSAA, 4X Anisotropic Filtering:
SM2.0 Gaming
128M = 641 rating
256M = 1279 rating (or 100% faster)
HDR/SM3.0 Gaming
128M = 554 rating
256M = 1063 rating (or 92% faster)

Under Windows XP Pro, I ran Prey 1.3 at 1440x900, 4X FSAA, 4X Anisotropic Filtering:
128M = 31 fps
256M = 46 fps (or 48% faster)

Cadaver · Jun 21, 2007, 07:31 PM

Originally Posted by mduell

May just be a confused driver, since the 8600GT supports 512MB RAM, but Apple only installs 256MB.

I would think this is correct. Apple specifies 128MB or 256MB. I suspect the Windows driver is incorrectly reading the VRAM value.

Geofries · Jun 21, 2007, 07:52 PM

See I DO believe that despite what so many are saying, the 256 DOES make a diff. I mean I just find it hard to believe a site that says "yeah, there's no performance diff. between the 128 and 256 cards". For VRAM, 256 is a heck of a diff from 128.

Especially under Windows, seeing as they don't appear to underclock like apple. When I do make the jump I'm going 256.

JoshuaZ · Jun 21, 2007, 10:45 PM

Originally Posted by buddy1065

I found this post interesting from here
MacBook Pro Santa Rosa 128MB vs 256MB - Benchmark compilation - Page 2 - Notebook Forums and Laptop Discussion

Quote:
More "VRAM Wars" -- 15" MacBook Pro 2.2GHz (128M VRAM) versus 2.4GHz (256M VRAM).

Under Windows XP Pro, I ran 3DMark06 at 1440x900, 4X FSAA, 4X Anisotropic Filtering:
SM2.0 Gaming
128M = 641 rating
256M = 1279 rating (or 100% faster)
HDR/SM3.0 Gaming
128M = 554 rating
256M = 1063 rating (or 92% faster)

Under Windows XP Pro, I ran Prey 1.3 at 1440x900, 4X FSAA, 4X Anisotropic Filtering:
128M = 31 fps
256M = 46 fps (or 48% faster)

Thats really really interesting. I'd love to see some more tests like this done. It could just be better windows drivers, or a better optimized version of the game for windows.

So far all the "Mac OS X" only bench marks have shown little to no difference in the two GPUs. The only difference has been the processor power, which bumps things up a small bit.

PaperNotes · Jun 22, 2007, 12:01 AM

Under XP/Vista the 8600 GT is fully clocked. You can overclock it too with right utilities. The drivers that comes with Tiger underclock the chip. You will see twice the performance under XP with intensive games.

Prey and 3DMark use very large and detailed textures, bump maps and light maps. These apps saturate 128MBs easily and need 256MB VRAM for best results. The days of 64-128MB VRAM for the latest games are gone. 256MB should be the minimum now.

tiger · Jun 22, 2007, 05:41 PM

New games would make good use of it but old games would probably do just fine on a 128. Hey my crappy on-board graphics C2D MacBook runs halo at full settings and it looks the same way it does on an X1600 iMac.

mduell · Jun 23, 2007, 07:12 PM

Originally Posted by PaperNotes

Under XP/Vista the 8600 GT is fully clocked. You can overclock it too with right utilities. The drivers that comes with Tiger underclock the chip.

Source?
Also, games are usually faster in XP than OSX even when at the same clockrates.

buddy1065 · Jun 24, 2007, 07:26 AM

FEAR tests on 2.4 Ghz
Santa Rosa MBP - F.E.A.R. benchmarks - NotebookForums.com

PaperNotes · Jun 24, 2007, 07:39 AM

Originally Posted by mduell

Source?
Also, games are usually faster in XP than OSX even when at the same clockrates.

Barefeats reports that the 8600M GT is much slower than the 7600m GT in the iMac confirming how underclocked it is in the MacBook Pro. That is in OS X only.

Barefeats also reports that games run not just faster but twice the speed under XP than OS X.

PC GAMING vs Mac GAMING
We installed a copy of Prey under both Mac OS X and Windows XP Pro. In our first test, we ran at 960x600 in windowed mode, max quality settings, 4X FSAA, 4X anisotropic filtering. Under Mac OS, the 17" MacBook Pro 2.4GHz scored 37fps. Under Windows XP Pro, it scored 73fps. Hmmm.

An XP utility reveals that the 8600M GT is almost fully clocked under XP at 470Mhz vs Nvidia's 475Mhz default factory clockspeed. In the 17" MacBook Pro under XP the card runs at 520Mhz.