Windows 7 x64 home premium using 4gb instead of 8gb installed??

[zejr_cg]

Hello guys,

My i5-760, with 1TB HD, ATI HD 5770, Toughpower XT 775W, M/B P755P-M. I bought 8GB Corsair Vegeance, but my Windows 7 x64 is saying (3.99 Usable).

I had done msconfig > Boot > the option maximum memory is not selected, BIOS also shows 4098 MBytes.

The CPUID software shows: 8196 MBytes installed, 4098 in slot #3 and slot #1 each.

So now I don't know what to do, as I'm running a x64 Windows 7 Home Premium, that support max 16 GB.

Any Ideas pls??

 

[GhislainG]

If the BIOS shows 4 GB, you can't expect Windows to see 8 GB. I checked the QVL and I didn't find any certified 4 GB modules. Does Corsair have your motherboard in the list of compatible motherboards? If so, I couldn't find it on their site.

Edit: What happens if you install a single module?

 

[zejr_cg]

I removed one module each time and both worked fine in different slots, showing 4GB, once I put them back together then I got 8GB (3.99 Usabele again) 🙁

Asus website says (4 x DIMM, Max. 16 GB, DDR3 2200(O.C.)*/1600/1333/1066 Non-ECC,Un-buffered Memory)

Bios still showing 4088 GB of RAM and windows 8 GB (3,99 Usable). Frustrating all this!!

 

[jaquith]

Assuming you meant the ASUS P7P55-M - http://www.asus.com/Motherboards/Intel_Socket_1156/P7P55M/#specifications

Use BIOS Version 0904 or 1001. Often the P55's (LGA 1156) have had 'bent CPU pin' problems causing this problem. Install the RAM in the 'Blue DIMM' slots.

First, in the BIOS check 'Memory Remap Feature -> Enabled' ; required for 64-bit OS and >4GB RAM.

Q1 - What changes have you made to the BIOS?
Q2 - What exact CPU?
Q3 - What exact set of 2x4GB Corsair Vengeance?
Q4 - Other than the 1 beep any other beeps during booting?
Q5 - Any Partitions with 32-bit? though the 3.99GB indicates a BIOS turned-off DIMM/Stick.

You can try the 'Black DIMM' slots to rule-out a bad DIMM slot.

 

[GhislainG]

I removed one module each time and both worked fine in different slots, showing 4GB, once I put them back together then I got 8GB (3.99 Usabele again) 🙁

Asus website says (4 x DIMM, Max. 16 GB, DDR3 2200(O.C.)*/1600/1333/1066 Non-ECC,Un-buffered Memory)

Bios still showing 4088 GB of RAM and windows 8 GB (3,99 Usable). Frustrating all this!!

Does memtest86+ show all memory and are there errors if you run it for several hours?