Another win XP memory issue

[Nooblie_One]

I know this has been covered often, but I think my situation might be a little different. I recently added another 2 gigs of memory to my system, both are Patriot 2x1gb kits at 800mhz and 4-4-4-12. I knew going it to this that 32bit Windows wouldnt see the full 4gigs but would probably only see about 3gigs, the thing is, it only sees 2gigs while other programs like CPU-Z as well as the BIOS sees that all of them are there. Also, the newer kit has EPP while the older one doesnt. I've also heard that SLI graphics cards can eat away at the limit, does a 7950gx2 do this as well?

PS I get the feeling that I might just be missing something very simple...

 

[Scotteq]

As far as the EPP: You shouldn't have a problem 'seeing' it - What'll happen is your comp should detect/default to a common setting instead of using the EPP.

What you're dealing with is a 4GB limit for address space to cover everything that needs to be communicated to: The ROM on your Mobo, HDD cache(s), video, etc... You said you know about it, but we can still use this to approximate what you theoretically should have access to.

I don't remember off the top of my head, but IIRC your 7950s are 500mb apiece. So that's a Gig right there, where a single would obviously only take 500MB of address space. Still... Given my personal experience of seeing 3.25 when I had 32 bit OS, that should only take you to something like 2.7GB. 700 meg is still unaccounted for. Would someone who's played with SLI be able to say if it grabs added chunks of memory addresses when enabled?? I haven't so I can't answer that, but it's a possibility.

The second thing to check: I know that on early DFI P35 Bios' there was a memory mapping issue. I think it only applied to P35, but you can/should check anyhow: http://www.dfi.com.tw/Support/Download/download_us.jsp?CATEGORY_TYPE=MB&INDEX_TYPE=MB&SITE=US

Something else to check - Some board/brands/chipsets have a 'memory remapping' function that may need to be enabled. Your profile says you have a DFI board - So you have an Award Bios yah? Or do you have the Genie one? I'm (screwing off...) at work now, so I can't go into my own (LP P35/Award) and look for you. But that's something to check on as well.

 

[Nooblie_One]

Well, it seems that the ram maybe defective, I tried running it by itself, it's rated at 4-4-4-12, at 800mhz and 2.2 volts, crashes at 5-5-5-15 at 800mhz and 2.2 volts after about a half hour, or 30 seconds under the orthos combined mem and cpu test, goes even sooner at the rated timings. Interestingly enough,the older memory was actually rated at 5-5-5-15 at 800mhz and 2.2 volts (this is what CPU-z reports the SPD as, even though the sticker says otherwise), buts seems stable and happy at 4-4-4-12 at 800mhz and 1.9 volts. Not sure if this solves my original problem, but will be RMAing it after the weekend and some further testing.

 

[WazzaUK]

Well, it seems that the ram maybe defective, I tried running it by itself, it's rated at 4-4-4-12, at 800mhz and 2.2 volts, crashes at 5-5-5-15 at 800mhz and 2.2 volts after about a half hour[/quota]

try running it at 4-4-4-12/800Mhz/2.2V.

 

[Nooblie_One]

I tried it like you suggested (running it again the the rated timings and speed), suprisingly it seems to running fine now. Thanks for the tip, i'll see how well it plays with the other two gigs now.