8600M GT for EXTERNAL monitor, 128 or 258?

[Donnacha]

I want to replace my desktop with a 15" SR Macbook Pro but I'm unsure if the 128mb 8600M GT will be enough to simultaneously power my MBP's screen and an external 24" Dell.

I will be using it for coding, Photoshop, Web Design and surfing. I might play a game occasionally but it's by no means an important consideration, I have consoles for that after all. I will probably want to do some video-editing at some point but I'm not talking major, high-def stuff, just the usual nonsense for YouTube etc.

The reason I'm considering the 128mb card, rather than the 256mb, is the astonishing price gap between the two 15" MBPs.

The low-end 15" MBP, once upgraded to 160GB, is £1349.

The high-end 15" MBP is £1599.

All that £250 difference, almost an extra 20%, gets me is a .2Ghz faster CPU and an extra 128mb of video card memory!

Everything else appears to be identical.

I'm not usually a guy to stint on his toys but I'm seriously questioning if that extra video memory will really make that much difference - by way of comparison, the Dell desktop I'm currently using has a really old GeForce FX 5200 64mb video card and seems to be doing an OK job of running the 24" Dell at a lower-than-native resolution of 1600 x 1200...

... surely the more modern 8600M GT's 128mb will manage the Dell's native 1920x1200 and the MBP's native 1440 x 900 with ease?

Am I being wildly optimistic here? Will the 128mb be fine or should I shell out for the 256mb?

Would very much appreciate any advice, thanks.

PS I should also probably mention that I want to use the 24" pivoted into portrait position (ideal for surfing and working on documents), so, it's actually 1200x1920, I presume that Macs can handle that as easily as PCs.

 

[Fearless Leader]

the only difference is the ability to load larger textures in games or 3D renders, the 128 is fine. Unless you want the extras of the 256, but 128 and 256 will make very little difference in your case.

edit: I ran a 23" 1900x1200 and a 1280x1024 or something like that at the same time on my nvidia fx 5200 with 64mb or video ram, everything was fine... except WoW and heavy motion work. And thats an old card.

 

[ziutek]

I also have the same concern. I have a 30" monitor and I'm debating whether to go with the 128 mb or 256 mb graphics card. Although there is little improvement between 128 and 256 in most applications, spliting 128 mb between two monitors seems like it would impact performance much more.

By the way, I do play games occasionally, but I'm not a hard core gamer. I also plan to use programs like Solidworks (through bootcamp) and other CAD programs so I'm assuming that the amount of memory might effect performance somewhat in such applications. Is there anyone who would be willing to benchmark their macbook pro w/ 128 mb connected to a 30incher?

 

[Donnacha]

@Rokem: thanks, I appreciate it.

@ziutek: from Rokem's post and having now gone back and read every thread on this issue over the last year, the consensus seems to be that any MBP is well-capable of running anything up to 2(!) 24" 1920x1200) external monitors - of course, you need a Matrox splitter to divide the dual-link DVI signal but the point is that the MBP can serve up the pixels without any problems. It will manage your single 30" without any problems at all.

The extra video memory only really matters if you need to display a lot of textures at high frame-rates i.e. games, but even the 128 should be fine for most games at reasonable screen sizes.

I will be going for low-end MBP, upgraded to 160GB 5400, and put the £250 saved towards my next laptop in 2 or 3 years.