[PewterScreaminMach]

I recently purchased some new OCZ 4GB (2x2GB) PC6400 from Newegg and installed it on my computer today. I plugged it in exactly the same way as before and the computer starts up and runs fine. The only issue is that when I go to Control Panel and System, it only shows as 2.5GB of RAM. Before this, I had 2GB (2x1GB) of the same OCZ dual channel memory installed and it showed fine as 2GB. Any thoughts on this?

Also, the other question I had that's not an issue but just makes me curious is that the memory is sold as 5-4-4-2T timing, I believe (does that sound right?) but on my startup screen where it shows the timings, it says 6-6-6-2T. What is the reason for this? I know the memory I got is marked the same as it was on Newegg, so it just seems to be running better. Is this normal?

Thanks!

Oh and my computer was built by myself (a hobby but I'm still a bit of a newb). Specs are below and I can post up any other info if needed:

XFX nForce 680i LT SLI Socket 775, Intel Core 2 Quad Q6600 2.40GHz, (now) 4GB DDR2 PC6400, ATX Mid-Tower Case, 600 Watt Power Supply, Seagate Barracuda 7200.10 500GB Hard Drive - 7200, KFA2 GeForce 8800 GT Overclocked Video Card - 512MB DDR3, XP Pro

[Bubba]

Unless that XP pro is a 64bit OS then you won't see all 4GB's of RAM. You should see 3.5 though i think...........

[Carbon]

3.5 on x32 - 1GB VRAM = 2.5GB regular addressed ram. Go to x64 and you'll get all 4GB.

Just fix the timings manually in the BIOS.

[ilop12]

get vista home premium 64 bit to get all 4gb you can get XP 64 bit but you can get vista on newegg for less and vista is more than 100% better. make sure that all the timings and voltages are the same. dont play around unless you are sure because you can fry your ram/motherboard

[PewterScreaminMach]

How exactly do I set all of the timings and voltages? And how do I know what voltages to set it to? I know the timings because they were written on the RAM itself.

And what do you mean by 3.5 - 1GB VRAM?

Thanks for the help, guys!

[PewterScreaminMach]

In case it helps, here's the memory I bought (got it from Tigerdirect, not Newegg btw): http://www.tigerdirect.com/applicati...=WEBLET03ORDER

[PewterScreaminMach]

Hmm, another interesting idea. I read in this Microsoft article http://www.microsoft.com/whdc/system...AE/PAEmem.mspx that your virtual memory is limited in XP Pro to 2GB, but you can "flip" a switch in the boot.ini file to allow it to access 3GB VRAM for applications. Is this something I shouldn't do? Could it cause other problems? Basically, the computer runs fine on XP Pro the way it is, I just wanted a little more memory for when I'm running a bunch of programs at once (Photoshop, Dreamweaver, Fireworks, IE, iTunes, audio recording software, etc). I'm not going to buy a new OS just to get another GB of memory, but if I can somehow make more available without an issue, I'll give it a shot.

I'm trying to read up on what I can rather than just relying on everyone's responses on a forum, but sometimes I don't quite understand everything from reading an article.

[Bubba]

That's the way to do it, read and ask. To set your memory timing:

I have a 790i so I am hoping your BIOS reads the same as mine lol.

Get to BIOS, (if you don't know how, ask), in BIOS scroll down to Advanced Chipset Features, hit enter:

Scroll down to FSB & Memory Config, hit enter:

Scroll down to Memory Timing Setting, change that to expert.
You should see timings below, change those values to 5-4-4-15 (there should be 4 values, not 3, and the last value, 15, I got from the memory link you provided in your OP)) and then 2T. Ask Carbon about the T2 thing. I have to use 2T because I have 8GB's of RAM, but I'm not sure you have to use 2T for 4. But then on the link you provided, it said T2. I just don't know enough about that to advise you.

I don't know about any "switches to flip" so again I won't offer advise there lol.

Hope the steps to change the timings helps though.

[PewterScreaminMach]

Hey man, thanks for the response. I actually figured it out right before you posted that and was debating the 1T vs 2T thing as we speak. Another question, is there a standard program most people use to benchmark and performance test their memory? I remember seeing some names but can't remember them.

[Bubba]

rIGHT HERE, YOU HAVE TO MAKE A BOOTABLE DISC TO RUN IT, AND IT TAKES A LONG TIME SO DO IT AT NIGHT LOL. Crap, caplock, too lazy to fix it.

http://www.memtest.org