Hello, first sorry for my english. A salesman told me that these memories would work correctly with speed above 2000MHz.
But I'm not getting. At most, without conflict, I am able to 1600Mhz. They are in the black slot. Can anybody home a light at the end of the tunnel?
Thank you, Leandro.
 
TY VistaHead!!!
QuadCore Intel Core 2 Q9400, 2666 MHz (8 x 333)
132-YW-E179-FTW
G.SKILL RipjawsX F3-17000CL9D-8GBXM (at 1600Mhz with 8G -  2x4G)
ATI Radeon HD 4800 Series  (1024 MB)
Windows 7 Ultimate 64 bits

Welcome to the forum!  First off, the RAM that you are using is not designed for five generations old technology.  It is designed for, and I quote,"Designed for 2nd Generation Intel Core Processors and Z68/P67 platforms".  Secondly, while some folks can run 4GB RAM modules on the 790i series boards, some cannot.  The boards "officially" support a maximum of 2GB RAM modules per slot.  Thirdly, it would help if you would edit your first post, and list all of your hardware.

ok thanks. already edited post.

Please completely fill out the below BIOS template to include the numerical values provided for all auto settings in your BIOS.
BIOS Version: 
**System **
CPU Freq, MHz: * GHZ
FSB Reference Clock, MHz: ****
CPU Multiplier: [*X]
PCle x16-1 & 16-2, MHz:  [100]
PCle x16-3, MHz:  [100]
SPPc->MCP Ref Clock, MHz:  [200]
nForce SPP --> nForce MCP:   [5X]
nForce SPP c-- nForce MCP:   [5X]
**Spread Spectrum**
CPU Spread Spectrum: [Disabled]
HT Spread Spectrum: [Disabled]
PCle Spread Spectrurn(SPP): [Disabled]
PCle Spread Spectrurn(MCP): [Disabled]
SATA Spread Spectrum: [Disabled]
**FSB & Memorv Config**
FSB - Memory Clock Mode: [unlinked]
FSB - Memory Ratio:
FSB (QDR), MHz: [****]
Actual FSB (QDR), MHz: ****
x MEM (DDR),  MHz: ****
Actual MEM (DDR), MHz: ****
P1: [AUTO]
P2: [AUTO]
**Memory Timing Setting**
Memory Timing Setting: [manual]
tCL (CAS Latency): *
tRCD: *
tRP: *
tRAS: *
Command Per Clock: [*T]
** Advanced Memory Settings **
tRRD: [Auto]
tRC: [Auto]
tWR: [Auto]
tWTR: [Auto]
tFAW: [Auto]
tREF: [Auto]
tRFC:
**System Voltages**
VDroop Control:
CPU Core: [*]
CPU FSB: [*]
Memory: [*]
nForce SPP: [*]
nForce MCP: [*]
CPU PLL:
GTLVREF Lane 0: [Auto] 
GTLVREF Lane 1: [Auto]
GTLVREF Lane 2: [Auto] 
GTLVREF Lane 3: [Auto] 
**CPU Configuration**
Limit CPUlD Maxval: Disabled
Intel Speedstep: Disabled
xPPM Mode: [Native]
CPU Thermal Control: [Disabled]
C1E Enhanced Halt State: [Disabled]
Execute Disable Bit: [Enabled]
Virtualization Technology: [Disabled]
CPU Core 0: [Enabled]
CPU Core 1: [Enabled]
CPU Core 2: [Enabled]
CPU Core 3: [Enabled]