How do you know if your ram is compatible with your other ram?

[star72]

So I have a 16.0GB Dual-Channel DDR3 @ 798MHz (11-11-11-28) across 2 channels (2x8) and since i found 2 ram sticks (Elpida 2gb RAM DDR 2RX8 Pc3-10600u-9-10-b0) lying around my room, I don't know if its compatiable with my current ram cause last time on my old pc when i added the ram (Elpida 2gb RAM DDR 2RX8 Pc3-10600u-9-10-b0) to the pc which already have 2x4gb ram on it it started making beeping sounds. I just want to make sure that if there will be any problems If add these 2 4gb of ram to my pc .
Thank you

edit: my motherboard is a Intel® Desktop Board DQ77MK

[r.linder]

There shouldn't be any compatibility issues, most, if not all DDR3 should work on a DDR3 motherboard. However, putting different modules of different specs will typically run with the lowest available memory speed value and the highest latency value. DDR stands for double data rate, so both kits appear to be DDR3-1600, but all DIMMs will run at CL11 because one of your kits is CL11 while the other appears to be CL9.

[star72]

Originally posted by Escorve:

There shouldn't be any compatibility issues, most, if not all DDR3 should work on a DDR3 motherboard. However, putting different modules of different specs will typically run with the lowest available memory speed value and the highest latency value. DDR stands for double data rate, so both kits appear to be DDR3-1600, but all DIMMs will run at CL11 because one of your kits is CL11 while the other appears to be CL9.

so do you think its worth the sacrafice for 20gb of ram?

[_I_]

all ram can work together, but will be limited to the lowest speed and highest timings

1600 cl11 (1600/11=145) is very sad ram to begin with
generic 1333/9 = 148 is slightly better

use cpuz spd tab to check its xmp/spd profiles, if it has a 1600 profile with lower timings use that
(on intel ddr3 boards make sure its 1.5v or lower profile)

[star72]

Originally posted by _I_:

all ram can work together, but will be limited to the lowest speed and highest timings

1600 cl11 (1600/11=145) is very sad ram to begin with
generic 1333/9 = 148 is slightly better

use cpuz spd tab to check its xmp/spd profiles, if it has a 1600 profile with lower timings use that
(on intel ddr3 boards make sure its 1.5v or lower profile)

I dont get it, that sounds too complicated

[_I_]

https://www.cpuid.com/softwares/cpu-z.html
‎
post a screenshot of its spd tab with each dimm selected if they are different

[star72]

Originally posted by _I_:

https://www.cpuid.com/softwares/cpu-z.html
‎
post a screenshot of its spd tab with each dimm selected if they are different

is this after i add the 2x4gb ram or before?
heres before: https://imgur.com/a/qaTvB2Z

[tacoshy]

Originally posted by Escorve:

There shouldn't be any compatibility issues, most, if not all DDR3 should work on a DDR3 motherboard.

Small exeption as you have to look between DDR3 and DDR3L. But beside of that yeah

[_I_]

thats a ddr3l kit (low voltage 1.35v)
(mhz x 2 = ddr speed)
its 1533 cl10 (1533/10=153) profile is slightly faster, but not by enough to make a real world difference

its 1200 cl8 (1200/8=150) is about the same too

if you need more ram, put them all in, ddr3l can run at higher voltage with no problems
and the other kit will be faster but run at the lower ones spec

[tacoshy]

Originally posted by _I_:

if you need more ram, put them all in, ddr3l can run at higher voltage with no problems
and the other kit will be faster but run at the lower ones spec

depends on the chip.

you're right that DDR3L is rated for 1.35V while DDR3 is 1.5V. However with XMp some DDR3 go up to 1.65V while most DDR3L (not all) are fine with 1.5V.
However less DDR3L are fine with 1.65V

[Bad 💀 Motha]

Some boards also don't like when you populate all 4 dimm slots, I would just stick to which ever ram is faster and not mix them. If the older ram is 1333 then it will force all installed ram to run at 1333. Best bet is the current 2x8gb ram and then enabled xmp profile for said ram in bios

[[☥] - CJ -]

You wont gain anything by adding a small amount of crappy RAM to an already 16GB RAM setup
16GB is plenty