I upgraded memory for an am3 785g board. Is it working properly??

mikesphat

Member
Mar 4, 2001
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0
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Athlon II X3 445 3.1 GHz - unlocked 4th core
ASUS M4A785TD-M EVO bios 2004
SPARKLE Calibre GeForce GTX 560 (Fermi) 1GB
Seagate Barracuda 7200.11 ST3160813AS 160GB 7200 RPM 8MB Cache SATA 3.0Gb/s 3.5"
FirePower ModXStream Pro 700MXSP 700W 80Plus Semi-Modular High Performance ATX PC PSU
Win7 Pro 64bit

old ram:
G.SKILL Ripjaws 4GB (2 x 2GB) DDR3 1333 (PC3 10666) F3-10666CL8D-4GBRM Dual Channel Kit (blue color)
Timing 8-8-8-24
Cas Latency 8
Voltage 1.5V

newer/upgrade ram:
G.SKILL Ripjaws X 16GB (2 x 8GB) DDR3 1333 (PC3 10666) F3-10666CL9D-16GBXL Dual Channel Kit (red color)
Timing 9-9-9-24
Cas Latency 9
Voltage 1.5V

Street Fighter V just came out and recommends 8gb, so I thought eh I only have 4 lets just splurge and get 16. It will make sfv more solid and windows snappier. I didn't see the part in manual where it says, no bigger than 4gb dimms per slot until I recieve the ram yesterday. Pcpartpicker said this was compatible ram. I had the old ram in dimms a2 and b2(black slots) and sfv seemed to play medium settings solid.

Friends tells me ram should of been in dimm a1&a2(channel A; one black, one blue slot). So I install new ram that way. bios says 16gb. post says DDR3 1333. win7 sits at 'now loading windows' for about 2 minute. I try only one in a2. I get to desktop but nothing feels quicker maybe slower. I try a1 and b1(blue slots), manual says: "Supports one pair of modules inserted into either the blue slots or black slots as one pair of dual-channel memory configuration." I make it to desktop and it still seems lil slower and no improvement. SFV in medium was dropping some fps where the old ram didnt.

Is this ram truly compatible and/or functioning properly as the manual says up to size 4gb dimms only? I figured it wouldnt fully boot if it wasnt compatible. Is it slower because timing is higher? But it is 4gb vs 16gb. I was thinking of trying to send it back and get 2x4gb or 4x4gb of lower timing ram. Manuals says I can have 2 pairs of dual-channel memory config. BIOS updates for mobo only mention cpu support and stability improvements.

Am I expecting too much for this old system? I thought 16gb would perk it up a small bit noticeable. sry for long story. thx.

p.s. g.skills site seems to only mention m5 mobos when you select 785g chipset ...when looking for what I would think is compatible ram for my mobo. guess im outdated (

p.p.s. im reading about something of a misprint in the manual about where to set 2dimms for dual channel for the atx version (i guess they are similar; -v instead of -m) of this mobo. im reading you should use the black slots like i was for the older ram.
 
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VirtualLarry

No Lifer
Aug 25, 2001
56,343
10,046
126
As far as I know, there is no issue in general with using 8GB DIMMs on an Athlon II-class CPU in an AM3/AM3+ mobo. Though, you might need a BIOS flash to take full advantage of it.

Windows' Control Panel System info should tell you if all of the RAM is recognized by Windows. If it says 16GB RAM, 8GB unusable, then you have a problem.
 

myocardia

Diamond Member
Jun 21, 2003
9,291
30
91
The new RAM was slower not because of the slight difference in timings, but because you were running it in single-channel mode. You were getting exactly half of the bandwidth you would in dual-channel mode. This is identical to forcing your RAM to run at half speed (DDR 667 as opposed to DDR 1,333), as far as the performance you will get from it.

edit: Just to clarify, each channel of your 1,333 Mhz RAM gives you 10,666 MB/sec of bandwidth. Two channels then will be 10,666 MB/sec x2, or 21,332 MB/sec.
 
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Elixer

Lifer
May 7, 2002
10,376
762
126
If the manual states you can only use 4GB sticks, then, you could be having memory controller issues.

Run memtest86+ overnight, and see if it passes. Should be 0 errors.

Lots of the old mobos don't like the higher density RAM either.
 

VirtualLarry

No Lifer
Aug 25, 2001
56,343
10,046
126
If the manual states you can only use 4GB sticks, then, you could be having memory controller issues.

Run memtest86+ overnight, and see if it passes. Should be 0 errors.

Lots of the old mobos don't like the higher density RAM either.

But... the memory controller is on the CPU, and AM3 CPUs handle up to 16GB sticks.