Mobo with onboard graphics or separate card?

[Deisel Weisel]

A new build for a work computer that will also be used for video work in my spare time, including some encoding and editing of HD stuff. Picked this CPU as value-for-money: AMD Athlon II X4 635. Now I need a mobo, but do I go for integrated graphics, like the 785G boards, or separate graphics card? I don’t play games.

[lenti_75]

You could use it with onboard graphics, but it's always better to have it separate; even the cheapest video card is better.
If the size of the mobo is not an issue, pick a full ATX and a cheap video card.

[pepegot1]

Separate video card for flexibility and reliability.

[Constant Gardener]

I have to disagree - 785G boards are quite adequate for most purposes, and they conveniently come with a PCI-16 slot in case one suddenly develops the urge to play Crysis. Don't buy a video card until you're convinced you need one. Just be aware that most integrated boards only let you run one analog display and one digital display - not two - which is the only reason I have a 2600XT video card on my "work" computer.

[usually_quiet]

Get a discrete video card if you want to encode video with an application that can use the GPU as well as a CPU.

Onboard video is fine for general-purose computing. I have been using a MSI 785GM-E65 mobo and no video card for about a year. It works just fine for word-processing, web-browsing, TV, watching DVDs, and theoretically Blu-Ray, though I haven't tried that yet.

You could get a motherboard with integrated video and see if it is enough. It doesn't add much to the cost of the motherboard, and it is nice to have a back-up if the discrete video card fails.

[MOVIEGEEK]

Another nice thing about a dedicated videocard is it has it's own memory, onboard shares your RAM.

[edDV]

"Editing HD stuff" needs more detail.

[usually_quiet]

Another nice thing about a dedicated videocard is it has it's own memory, onboard shares your RAM.

Some motherboards, like mine, include "sideport memory" for the onboard video, usually 128 MB.

I don't think the amount of dedicated memory that the video card has matters much anymore when not playing games or performing some othe GPU-intensive functions, where having plenty of memory reserved just for the video card improves efficiency and speed. Under some circumstances, more memory for the video card also means less available for everything else.

For example, a 32-bit OS, can address 4 GB of memory, but that figure includes the default address space automatically alloted to the video card, PCI bus, BIOS, and a couple of other things I can't recall. The figure I saw for Windows 7 32-bit said 3.2 GB or less of installed RAM will be usable, and that figure goes down as the size of the video card's dedicated memory goes up.

64-bit Windows 7 Home Premium can access up to 16 GB (which is all many motherboards support). The Business and Ultimate 64-bit editions of Windows 7 supposedly can address up to 192 GB of memory. Given that, who cares about sharing a little with the video card if squeezing as much speed and efficiency as possible out of the video card isn't critical?

[jagabo]

I don't think the amount of dedicated memory that the video card has matters much anymore when not playing games or performing some othe GPU-intensive functions

If the GPU is using the CPU's DRAM as a frame buffer memory bandwidth is being sucked away to refresh the display. With a 1920x1080, 32 bit, desktop running at 60 Hz that's about 500 MB/s of memory bandwidth just to display a static desktop. And since the CPU is most likely accessing different parts of memory than the GPU there are further delays waiting for DRAM to change pages. So integrated memory using the same DRAM as the CPU has a significant impact on performance. The last time I saw real numbers it was around 15 percent. That was quite a while ago (10 years?) so the situation may have changed a bit. On the one hand memory is faster. On the other hand we're running larger desktops with more color depth and more GPU effects.

[Nelson37]

The difference in cost is minimal, considering JUST the mobo. If you buy a mobo with no graphics, then you MUST purchase a card to be functional. If you get one WITH graphics, then you are functional and can always upgrade. Lower total up-front cost.

Down the road, if you sell or exchange this PC you can remove the video upgrade and still have a functional PC, IF there is mobo graphics.

[usually_quiet]

I don't think the amount of dedicated memory that the video card has matters much anymore when not playing games or performing some othe GPU-intensive functions

If the GPU is using the CPU's DRAM as a frame buffer memory bandwidth is being sucked away to refresh the display. With a 1920x1080, 32 bit, desktop running at 60 Hz that's about 500 MB/s of memory bandwidth just to display a static desktop. And since the CPU is most likely accessing different parts of memory than the GPU there are further delays waiting for DRAM to change pages. So integrated memory using the same DRAM as the CPU has a significant impact on performance. The last time I saw real numbers it was around 15 percent. That was quite a while ago (10 years?) so the situation may have changed a bit. On the one hand memory is faster. On the other hand we're running larger desktops with more color depth and more GPU effects.

Whatever the small loss of performance is attributable to using onboard graphics amounts to, it doesn't seem to be a problem in my case. The Windows 7's Windows Experience rating system gives my onboard graphics + sideport memory a 4.4 score for Aero, which is more than enough for most purposes. I used the Windows Experience Index's "View and print detailed performance and system information" feature to look at how the memory is allocated for video in my system. This is what it said:

Total available graphics memory 1023 MB
Dedicated graphics memory 384 MB (384 MB = 128 MB side port memory + 256 MB reserved by default)
Dedicated system memory 0 MB
Shared system memory 639 MB

I would need to add a VGA card if I had to run 2 monitors using DVI or HDMI, or I wanted to use a GPU-enabled encoder, or if I took up gaming, CAD, advanced photo editing, or 3D modeling, but I am unlikely to do those things any time soon. A discrete card might make HD video a little crisper, but I'm satisfied with what I see now.

Whether integrated video is good enough for the OP depends on him.

[jagabo]

Whatever the small loss of performance is attributable to using onboard graphics amounts to, it doesn't seem to be a problem in my case. The Windows 7's Windows Experience rating system gives my onboard graphics + sideport memory a 4.4 score for Aero

It's the CPU that's burdened by the onboard graphics continuous DRAM access. In your case, with the frame buffer in the sideport memory, the burden us much lower.

Whether integrated video is good enough for the OP depends on him.

Yes. For many porposes integrated graphics are fine and the DRAM burden doesn't matter.