What specs must I match to have "matched" RAM?

luckycharms

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May 16, 2009
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Hi Folks,

I have a Dell M3800 with an 8GB stick in it (specs below). I'm looking to up it to 16GB, and I'm wondering what specs I need to match in order to have "matched" RAM? Do I need to get the exact model number the same? Timings? Any help greatly appreciated. Thanks!


Code:
Memory SPD
-------------------------------------------------------------------------

DIMM #				1
	SMBus address		0x50
	Memory type		DDR3
	Module format		SO-DIMM
	Manufacturer (ID)	Samsung (CE000000000000000000)
	Size			8192 MBytes
	Max bandwidth		PC3-12800 (800 MHz)
	Part number		M471B1G73DB0-YK0  
	Serial number		37DAEF0B
	Manufacturing date	Week 13/Year 14
	Number of banks		8
	Nominal Voltage		1.35 Volts
	EPP			no
	XMP			no
	AMP			no
JEDEC timings table		CL-tRCD-tRP-tRAS-tRC @ frequency
	JEDEC #1		5.0-5-5-14-19 @ 380 MHz
	JEDEC #2		6.0-6-6-16-22 @ 457 MHz
	JEDEC #3		7.0-7-7-19-26 @ 533 MHz
	JEDEC #4		8.0-8-8-22-30 @ 609 MHz
	JEDEC #5		9.0-9-9-24-33 @ 685 MHz
	JEDEC #6		10.0-10-10-27-37 @ 761 MHz
	JEDEC #7		11.0-11-11-28-39 @ 800 MHz
 
Solution
Matching frequency, voltage, and timings will help. Ideally, you'll want a stick of the exact same model number.

However, there is never a guarantee that mixing memory kits will work. They often don't for no apparent reason even with two modules of the same model number. Raising voltage manually in the BIOS a bit can help, but there's no guarantee.

The best thing would be to buy a new 2x8GB kit and sell the current module you have. That guarantees compatibility. Modules in kits are tested to be sure they work together.

http://www.newegg.com/Product/Product.aspx?Item=N82E16820148730&cm_re=BLS2K8G3N169ES4-_-20-148-730-_-Product

promo code for discount:
EMCAVPA37
Usually any 8gb ddr3 stick will do, and the bios will adjust the timings and speed and will make both run at the slower speed /timings.
However these days I have seen a few people coming with problems such as two different sticks not working (also it is not recommended that you use diff sticks)

So I would strongly recommend that you buy the exact same Stick and considering its a ddr3 pc12800 it will be available easily.

Hope this helps!
 
Matching frequency, voltage, and timings will help. Ideally, you'll want a stick of the exact same model number.

However, there is never a guarantee that mixing memory kits will work. They often don't for no apparent reason even with two modules of the same model number. Raising voltage manually in the BIOS a bit can help, but there's no guarantee.

The best thing would be to buy a new 2x8GB kit and sell the current module you have. That guarantees compatibility. Modules in kits are tested to be sure they work together.

http://www.newegg.com/Product/Product.aspx?Item=N82E16820148730&cm_re=BLS2K8G3N169ES4-_-20-148-730-_-Product

promo code for discount:
EMCAVPA37
 
Solution
Even if you buy the exact same model, they are not guaranteed they will work together. RAM sticks are only assured to work together if they are sold as a 2-pack kit (after testing by the manufacturer). You should consider buying a new 2 x 8GB kit.