Graphics card function...

First of all, my specs:

Motherboard: Gigabyte GA-K8N-SLI

CPU: AMD Athlon 64 X2 3800+

RAM: 3GB DDR SDRAM (2 512MB and 2 1GB sticks, using all four slots)

GPU: MSI Nvidia 9400GT in 1st SLI slot (I'm only using one slot)

HDD: 2 500GB WD HDDs


Now, my questions. I have two displays connected to my GPU, a 47" LCD 1080p TV and a 24" 1080p monitor. The displays are cloned, and for some reason, my TV (connected via the DVI port using a DVI-HDMI converter) thinks it's the primary display, while the monitor is connected via HDMI. Is there any way to change it so my monitor is primary (not just within Windows... BIOS, etc. shows up only on my TV when booting)?

Secondly, my computer won't play 1080p videos, whether they're MKV, AVI, etc. file types. The display(s) freeze and skip through. I can play 720p just fine. Is it possible for me to fix that? Is that because I have an incapable graphics card, or is it due to my aging CPU, or what? I've tried Media Player Classic, Kmplayer, WMP (latest), Winamp, etc. No dice.

IF the above problem is due to my GPU or CPU, is it possible to overclock one or both, or add a second card and use the SLI, or something, to allow me to actually watch 1080p videos?

My final question(s): what, EXACTLY, does the GPU do? What are the benefits of a better graphics card/running two graphics cards?

Any help would be greatly appreciated!

 

The primary is typically determined by the connection. So to make the monitor the primary, you need to switch the monitor and TV cable connections on the card. BUT, if the only problem is during boot, I would leave it.

The CPU has nothing to do with your resolutions.

You did not specify which 9400GT card you have. MSI makes several 9400GT cards, some with only 256MB, some with 512MB and one with 1GB. If yours only has 256MB, that is a big (or tiny) bottleneck. But even the 1GB model would be struggling as the 9400GT is not a very powerful GPU to start with and I suspect that is most of your problem - especially when trying to drive two monitors, and two monitors of such a drastic difference in display size. I hope at least they are set to the same resolutions, but I suspect they are not, since one is a TV and probably has a different "native" resolution than the monitor. But, let's face it, when you can get a 9400GT with 512Mb of RAM for only $19 (after mail-in rebate), you should not expect much in terms of performance.

A GPU is a CPU dedicated to and optimized for graphics processing. It is the heart of the graphics card. A better GPU means faster and more capable processing. Generally, the more you can budget to graphics, the better. (See Toms Hardware, Best Graphics Cards for the Money - June 2010).

Two cards take you into the realm of serious gaming (or 4 monitors). You probably don't need two cards, just a better single card. Next to a good supply of system RAM, a good graphics solution is probably the most critical component for good over all computer performance in today's graphics oriented world - even above the CPU.

WARNING! Graphics cards are power hungry! Do not attempt to upgrade your graphics until you are certain you have an adequate power supply from a reputable maker. It is typical to require upgrading the PSU before upgrading the graphics card. This is especially true is other hardware has been added, such as more RAM, since the system was first purchased. Also, most of the better cards require 1 or 2 additional power connections which many older PSUs don't provide.

Finally, I have been running with 2 monitors for years and I have found UltraMon to be indispensable. It is not free, but still worth it. And it has an option to change the primary monitor.

 

Thank you very much for that information!

I completely built the system myself, the power supply is either 600W or 650W CONSTANT rated (not peak), and a good manufacturer... I honestly can't remember the make/model, since I bought it a few years ago. I just transferred my entire system into a new case (full tower... AWESOME!), but of course didn't pay any attention to the PSU when I transferred it. It's modular, and I'm sure has enough juice/connections for a better GPU.

The GPU I have is "MSI N94GT-MD512 GeForce 9400 GT 512MB 128-bit GDDR2 PCI Express 2.0 x16 HDCP Ready Low Profile Ready Video Card". Newegg's price is $50 (before rebate).

Link: http://www.newegg.com/Product/Product.aspx?Item=N82E16814127412

Both displays are running at 1080p resolution (like I said, they're cloned displays, so resolutions, etc. are exactly the same).

I'm getting UltraMon, per your suggestion.

I would really like to get a good graphics card, since that seems to be the heart of the issue. Suggestions would be appreciated.

What I'm looking for in a new graphics card:

At least 2 HDMI inputs
A DVI input would be helpful, though not high on the list of requirements
Be able to play full 1080p video on both displays simultaneously with ease
Longevity -- I will be replacing my MB/CPU in the somewhat near future, and I want a GPU that won't out-date itself within the next few years.

I'm definitely an Nvidia guy, so no ATI! Thanks.

EDIT: I'm just starting a new thread for graphics card replacement suggestions, since you've really answered my questions brought up in this thread. Thanks again!

 

Well, you need to set a budget before asking for suggestions. And you still need to check out that Toms Hardware link.

You don't need DVI if you have HDMI. The video signal in the two is exactly the same.