DDR2-1066 windows XP detect only 2gb on 4gb

isrdum

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Hi
I bought OCZ (OCZ2P10664GK) DDR2 PC2-8500 1066 MHz Platinum Series 4GB(2x2048) Dual Channel Kit
My motherboard support these stick (M750SLI-DS4)
The BIOS detect de 4gb correctly
When I start CPU-Z, it recognizes my 4gb of RAM.
But Windows XP see only 2gb (system on control panel) and EVEREST too.
MAXMEM is not select
RAM voltage is 2.1V
They are on DUAL chanel and Unganged.
The computer never bug (no blue screen)
I try only one of them and they work great both.
What happen?
Thanks
 
Well the initial versions of XP wouldn't see anything past 2GB, but with the service packs usually you can see 3-3.5 GB depending on what other devices are using address space. What video card(s) are you using? Did you apply SP3?
 

isrdum

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Thanks for fast reply!!!
I have 2 X 9800GT 512mb SLI (EVGA and XFX)
Windows XP is up to date, SP3 is already installed.
All my drivers are the newest,
Thanks
 

4745454b

Titan
Moderator
Do you see exactly two, or two and change? I know windows needs to assign address space for I/O, what I don't know is how much it uses for each video card. It probably doesn't need the full 512MB per card, as the video card uses some of its memory for other things. (like applying AA/AF.) If windows does assign the full 512MBs, then there goes one gig. Add in other devices, I wouldn't be surprised to you that you have ~2.5-2.75GBs showing in windows.

If you have exactly 2GBs, I have no idea whats going on.
 
With the GFX cards eating 1GB, plus the normal 256MB reserved by the OS, that leaves us with ~2.75 total, so we have around 768MB of RAM missing on us.

You don't have a sound card or other device with RAM on it? Also, are you sure your 2 GTX's are only 512MB and not 1GB?
 

isrdum

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Hi
I bought, with this memory stick, one 30 gb solid state drive OCZ (SSD).
I don't know if this could be the problem!!!
My graphic cards have each 512mb, I cheack them again!
Thanks
 

isrdum

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Here what I got in my BIOS

SLI-Ready Memory Disable
Set Memory Clock Manual
Memory clock X4.00
DCTs Mode Unganged
DDRII Timing Items Auto

Memory Controller Freq. Auto
 

4745454b

Titan
Moderator
You have to enable something in the bios if the motherboard is to use more then 4GBs. The term can one of several different things, but it should say something about "extended". Its what you have to enable if you want to use 8GBs of memory. Depending on your bios, I'm wondering if its capping the ram at 2GB. If you can flip the value (turn it either on or off depending on what its current value is) you MIGHT see the ram.

 

isrdum

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I red a lot the manual with the BIOS!!! (5 time)
But this magic value seem to not exist!!
I red a lot of forum but no body can resolve my problem.
I don't know what to do, I waiting for bios update!
Thanks for your help
 

isrdum

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Here What I get with 3dMark06

Memory Slot 1/4
Installed Enabled Size 2.00 GB
Form Factor DIMM
Frequency 800.0 MHz
Slot A0 [Bank0/1]
Enabled Size 2.00 GB
Total Bit Width 64 b
Data Bit Width 64 b

Memory Slot 2/4
Installed Enabled Size 2.00 GB
Form Factor DIMM
Frequency 800.0 MHz
Slot A1 [Bank2/3]
Enabled Size 2.00 GB
Total Bit Width 64 b
Data Bit Width 64 b

But windows XP still see 2gb!!!!!!!!
 

isrdum

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Other thing

Total Physical Memory 1.98 GB
Free Physical Memory 1.49 GB
Total Pagefile Memory 1.84 GB
Free Pagefile Memory 1.52 GB

And I disable Virtual Memory!!!

Are these new information help you?