8GB vs 16GB and GPU Question

[-Church-]

I'm planning on upgrading from my 4 GB GieL R.A.M I have now since I seem to be using a whole lot of it while gaming and even while idle. (47% usage) (somewhere around 80% during intense gaming)

So I'm just wondering what would be worth it to get, 8GB of faster timed R.A.M or 16GB of slower timed R.A.M. Theres a 40 dollar difference with the 16 GB. I just don't think I'd be using that much even with hard-core gaming. I plan on running all the latest titles (BF3 etc) maxed out 1080p. Would it be worth it to get 16 GB? Or would it be better to grab another 8 GB kit down the road? Also if you have opinions on manufacturers pros/cons that would be helpful.

8 GB: http://www.newegg.com/Product/Product.aspx?Item=N82E16820233147

16 GB: http://www.newegg.com/Product/Product.aspx?Item=N82E16820145347

Also this is a bit off topic but I'm also upgrading from my 6870 to a 6970. But I have a choice I could either CrossFire 6870's or get a single 6970. From what I understand 6870s can have more performance than a single 6970 but XFire has some issues and doesn't always work as advertised. I myself haven't ever cross-fired and am a bit curious on whether or not its worth it. Also I've heard that you could unlock a 6950 to a 6970 so would that be worth it? I could XFire those if it worked but I've heard it's also unstable.

My rig configuration:

CoolerMaster Elite 430 (Case)
ASRock 870 EXTREME3
AMD Phenom II X4 955 Black Edition (@4.0 GHz OC) Cooled with CoolerMaster Hyper 212+
4 GB DDR3 @ 1600 MHz (9-9-9-28)
1 TB (500 GB x 2) Seagate 7200 RPM 32 MB (total) Cache (RAID 0)
XFX AMD Radeon HD 6870 1GB GDDR5 256 Bit (940 MHz/1150 MHz)
Windows 7 x64 Ultimate

Any thoughts or opinions are helpful.

 

[jjb8675309]

for gaming the 8 gigs of faster ram is the obvious choice but bear in mind you will see basically zero difference in actual gameplay imo over 4 gigs even, 8 gigs is nice to help with loading and maybe fix a hiccup or two but other than that it is pretty much still pointless in gaming.... I think Starcraft II was the game that would use up the most ram on my system where the usage goes slightly above 3 gigs and other than that it is usually under 2 gigs of usage...

in the end it is not wise to spend much money on ram but rather dump more money into the cpu or graphics subsystem, that is, in a purely gaming rig..

if your itching to upgrade have you considered an ssd? I got a crucial m4 64gb for around 100 and it works amazingly as an os boot drive, def worth it imo...


...also in the end the 16gigs of ram is a way better deal so id grab that if you go with a ram upgrade although you probably never use it unless you find some new usages for your comp outside of gaming....

 

[Leaps-from-Shadows]

8GB is optimal for gaming. You definitely will see differences in overall system performance as well as game performance. With more memory, games themselves as well as individual game levels will load quicker and you won't have as many graphical anomalies. Plus, you'll be able to multi-task more smoothly, switching back and forth without big pauses.

Why is that? Because it's not just Windows and the game itself that use up system memory -- the graphics card does too. With 8GB of system memory, your graphics card will be able to grab the maximum amount of it to store game textures so they are instantly ready for use, instead of having to grab them from the hard drive which is many many times slower.

My GTX 570 has 1280MB of its own graphics RAM, but it also grabs 2815MB of system RAM for use when gaming. That means it has a total of 4095MB of available graphics memory to use when I run games. If I only had 4GB of system RAM, the graphics card wouldn't be able to grab as much, and game performance wouldn't be as good.

To find out how much memory your graphics card is grabbing, go to the WEI window (right-click on Computer in the Start menu and choose Properties, then click on the WEI rating), then click on "View and print detailed performance and system information" on the right side.

Under the Graphics heading, mine shows:

Total available graphics memory 4095 MB
Dedicated graphics memory 1280 MB
Dedicated system memory 0 MB
Shared system memory 2815 MB

The dedicated graphics memory is from my GTX 570. The shared system memory is the amount the graphics card can grab while gaming. The higher, the better. Note that the shared amount won't go up when going from 8GB to 16GB of system RAM -- the graphics card does have a maximum that it can grab and it likely reaches that maximum at 8GB of system RAM.

 

[misry]

Get the 16G kit. Worse comes to worse you can setup a RAM drive to put your Windows swap file on. Speed is good.

 

[Snoop05]

Using system memory by gpu is thing you dont want. 1600MHz DDR3 running in dual chanell (128 bit bus width) mode gives you theoretical 25,6 GB/s bandwidth. Today GPUs have higher clocked GDDR5 and wider bus (256 - 384 bit) that can give you around 200 GB/s. 25,6GB/s is beteween CPU and RAM and theese 200+GB/s are between GPU and VRAM. If your GPU needs to use your system RAM (which is 8 times slower) it also need to transfer it thru PCIE bus which has bandwidth of 8GB/s (2.0) or 15GB/s (3.0). If such situation come, you will see huge fps drop.

Also about that RAM drive and swap (or pagefile as windows calls it) - its made for case you ran out of RAM. When your ram usage is nearing some percentage, (i dont know exactly how it its on windows, but i can control it on linux) lets say ~80%, windows will start moving older or unused memory blocks to pagefile on your storage device. I have a suspicion that it quietly tries to keep 1:1 copy of your ram even when you only use around 15% to prevent system hang when writing to hard drive. So lets say you have 16GB ram. With no pagefile or ramdrive, you have 16GB of 25,6GB/s memory. If you make 4GB ram drive on it, you have "only" 12GB. If you also use it for pagefile, everything that will be on your ram will be read and again written to that 4GB block and so wasting your 25.6 GB/s bandwidth in both directions (in and out) by having to reread and write its contents 2nd time.
Generaly, you will loose both ram capacity and speed.