system not detecting 4 gb ram

[vamsi23]

i recently upgraded to 4gb ddr2 ram and using XP 64-bit SP2 OS....Xp only recognizes 2.9GB. also when checking whether games are compatible or not using
systemrequirementslab.com it only shows 2.9GB of RAM. wat should i do to make my system recognize 4GB? i use asus commando motherboard. plz help and thx..

[rhitwick]

How many RAM sticks do u use? is it 2*2GB? Are all of them of same frequency.
Try upgrading XP to SP3.

And, do prodive ur full system config.

[Krazy Bluez]

If it's 64 bit then it should detect all the RAM...check if you're running in Dual-Channel Mode in BIOS...

[vamsi23]

its 2*2 GB ddr2 800mhz Transcend both same frequency....I use XP SP2 x64 OS...
ASUS Commando motherboard
Leadtek 8800GTS 640MB
Seagate 250 GB SATA2
Samsung SH-S223 SATA optical drive
Zebronics 500watts PSU
and how do I check whether its running in dual channel mode in bios??? previously I used 1*1GB ddr2 667mhz and it worked fine..I checked using CPUZ, it shows total size 4096MB in SPD tab, it shows correctly slot#1 2048MB and slot#3 2048MB

[Krazy Bluez]

Try booting with a live linux distro and check whether it is detecting the full ram or not