Will this 2 RAM work well together?

Here is a report from CPUz

DIMM # 1
SMBus address 0x50
Memory type DDR2
Module format Regular UDIMM
Manufacturer (ID) GEIL (7F7F7F1300000000)
Size 2048 MBytes
Max bandwidth PC2-6400 (400 MHz)
Part number CL5-5-5 DDR2-800
Manufacturing date Week 44/Year 09
Number of banks 2
Data width 64 bits
Correction None
Nominal Voltage 1.80 Volts
EPP no
XMP no
JEDEC timings table CL-tRCD-tRP-tRAS-tRC @ frequency
JEDEC #1 3.0-4-4-10-16 @ 266 MHz
JEDEC #2 4.0-5-5-13-20 @ 333 MHz
JEDEC #3 5.0-5-5-15-23 @ 400 MHz

DIMM # 2
SMBus address 0x52
Memory type DDR2
Module format Regular UDIMM
Manufacturer (ID) Kingston (7F98000000000000)
Size 2048 MBytes
Max bandwidth PC2-6400 (400 MHz)
Part number
Serial number DC1815E5
Manufacturing date Week 11/Year 09
Number of banks 2
Data width 64 bits
Correction None
Nominal Voltage 1.80 Volts
EPP no
XMP no
JEDEC timings table CL-tRCD-tRP-tRAS-tRC @ frequency
JEDEC #1 4.0-4-4-12-16 @ 266 MHz
JEDEC #2 5.0-5-5-15-20 @ 333 MHz
JEDEC #3 6.0-6-6-18-24 @ 400 MHz


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And what are the specifics that I should consider when adding a new RAM together with my old one? Thank you

They should work fine together, they have the same frequency and required voltage, although you may have to run both sticks at 6-6-6-18-24

You'll have to enter the BIOS and locate the memory settings, then change the latency timings to 6-6-6-18-24, make sure the frequency is 800Mhz and that the Voltage is 1.80V

Are they not working fine now? Seems like the PC boots fine if you got a CPU-z report.

And to answer your question, order DDR2 PC2-6400 if you want to add RAM. You can also go higher than 6400, but will see little advantage if you're adding it to the existing RAM.