8GB of ram only 7.5 usable...why not the full 8GB

[KWellon]

i just added another 4 gb of ram to my system and in the bios it say 8192 installed, 7679 usable and windows says 8gb installed, 7.5 usable. i know it's not much but i'm running a 64bit system, why isn't the full 8gb showing as usable???

Thanks for your time and for any and all input.
Kerry

 

[sub.mesa]

Probably because some reserved space after 4GiB. This was used by hardware and other legacy designs which didn't take into account RAM could ever rise beyond 4GiB (512K ought to be enough for everybody - right?)

 

[KWellon]

so can i resolve it and have the full 8 available or am i stuck with the 7.5??

 

[sub.mesa]

Depends on your motherboard, some properly support memory remapping. But most BIOS's don' t properly do this. Some even 'cap' the capacity to 4GiB even if you had 8 installed; just because the taiwan engineers (I ENGLUISH VERY GOOD SPEEK!!!) were to uneducated to come up with a proper solution.

One screw up in the past means you get alot of headaches in the future, if you have to stay compatible.

 

[IndyColtsFan]

What board do you have? If you have stuff like integrated graphics, that might be using shared memory and as a result, that's why you don't see the full 8 GB.

 

[sub.mesa]

That's another possibility yes, good one!

 

[KWellon]

thanks guys. i have an asus m2n-sli deluxe. no integraged graphics. but the max mem for this board is 8GB. does that mean that 8gb is the max the mem controller can handle even with my vid card included? i thought 64bit got rid of that issue...just confused now.

 

[Nothinman]

thanks guys. i have an asus m2n-sli deluxe. no integraged graphics. but the max mem for this board is 8GB. does that mean that 8gb is the max the mem controller can handle even with my vid card included? i thought 64bit got rid of that issue...just confused now.

If 8G physical is the max the chipset can address then you'll never hit the full 8G because some of those addresses are required for your hardware.

 

[Yellowbeard]

You could also try clearing the CMOS if you have not already. Depending on those hardware reservations Nothinman noted, you may free up some of it.

 

[tcsenter]

What graphics card do you have? Could be one of those Turbo Cache jobbies.

 

[TemjinGold]

To be honest I wouldn't sweat over it. Even if you DID recover the missing half a gig, you wouldn't notice one bit of a performance difference unless you are some seriously heavy Photoshopper...

 

[KWellon]

thanks for the responses guys. i actually tried updating my bios and that fixed it. now have the full amount available.

 

[Jacky60]

Depends on your motherboard, some properly support memory remapping. But most BIOS's don' t properly do this. Some even 'cap' the capacity to 4GiB even if you had 8 installed; just because the taiwan engineers (I ENGLUISH VERY GOOD SPEEK!!!) were to uneducated to come up with a proper solution.

One screw up in the past means you get alot of headaches in the future, if you have to stay compatible.

I think you'll find it's 'too' uneducated' not 'to' uneducated if you're in the business of English criticism. How's your Cantonese or Mandarin? I'd bet their English is better.

 

[sxr7171]

I think you'll find it's 'too' uneducated' not 'to' uneducated if you're in the business of English criticism. How's your Cantonese or Mandarin? I'd bet their English is better.

Yeah any day of the week.

 

[Emulex]

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