Can I use both DDR3 RAM of 1600MHz & 1333MHz

[Rajakrishnan]

I have upgraded my system Memory with Corsair Vengeance DDR3 8 GB (2 x 8 GB) with 1600MHz , I do have 4GB (2 x 2GB) with 1333MHz old ones unused

My Mobo ASUS Z97-A has 4 Memory slots. My doubt is ,can I use the additional 4GB RAM along with the existing 16GB (2 x 8 GB).

I tried to add the additional 4GB , but no success system not at all booting..

Below is the DRAM mapping
Slot A1 - Corsair 8GB
Slot B1 - Transcend 2GB
Slot A2 - Corsair 8GB
Slot B2 - Transcend 2GB

Suggest me a solution.

 

[TJ Hooker]

Mixing different memory kits, especially ones with different timings, is a crapshoot. Even if you do manage to get it working, you'll probably have to resort to running all the RAM at 1333 MHz.

16 GB is more than enough for the vast majority of people, so unless you have some specific application that you know requires more, I don't know if I'd bother.

 

[Ironsounds]

Hello... You will need to boot them all at 1333 first to get them working... shut off XMP (save&exit).
1) try resetting/clearing your CMOS MB memory to put BIO's into Memory search Mode... and with just the 2x2GB inserted.
2) Once you got them working (save&exit).
3) insert the 2x8gb into the MB and see if you can get them to Boot with the 2x2gb settings (save&exit).

 

[Rajakrishnan]

Mixing different memory kits, especially ones with different timings, is a crapshoot. Even if you do manage to get it working, you'll probably have to resort to running all the RAM at 1333 MHz.

16 GB is more than enough for the vast majority of people, so unless you have some specific application that you know requires more, I don't know if I'd bother.

I think Its better to stay with 16GB, which is currently sufficient for my work.
If i would prefer for upgrade in future , which would be the better option?
2 x 8GB with 1600MHz or different size 2 x 2/4 GB with 1600MHZ

 

[Ironsounds]

Hello... The same brand/Type 1600 will be the best for MB compatability... any combo size you want will work, no performance loss.

 

[TJ Hooker]

If you want to add more RAM in the future, your best bet would be to try and buy another kit of the exact same RAM you just bought. If that's not possible, I'd try and find another 2x8 GB 1600 MHz kit with the same timings (CAS latency, etc). But even if you get an identical kit, it's not guaranteed to work.

 

[photonboy]

Hey,
As said, 16GB should be plenty.

Don't risk system instability for what is unlikely to make any difference at all (which sometimes isn't detected with MEMTEST or similar diagnostics either so you can get data corruption over time and not know why). In fact, you may even LOSE a small amount of performance for some tasks.
http://wccftech.com/haswell-works-high-speed-ram-benchmarks-show-ddr31600-mhz/

I wouldn't buy faster memory, but it's worth reading the above. Note that it's proportional to the amount of CPU processing happening.

For example, going from 1600MHz to 1866MHz for Starcraft 2 gained about 5% at the same stock settings.

SC2 is very cpu intensive at times so most games likely don't benefit like this. Still, it's worth noting it can be beneficial at times so I wouldn't drop to 1333MHz.

The CAS value is also important, but I won't get into that here.

*Basically I recommend:

1) do NOT use the extra 4GB
2) set to XMP
3) update BIOS if newer exists
4) CPU overclock if applicable (may affect memory settings)
5) diagnostics:
a) memtest86.com (full pass, default settings)
b) Intel CPU diagnostic https://downloadcenter.intel.com/download/19792/Intel-Processor-Diagnostic-Tool

 

[photonboy]

Future upgrade?
Unless you edit video, or use some combination of software that benefits from more than 16GB then upgrading won't help.

But... to answer your question on that.

*In general:
a) don't mix memory (use same exact model number)
b) ideally buy as a single kit (a 2x8GB kit later of the exact same model number can actually be slightly different, though chances of failure are likely slim, and worst-case is likely just a manual tweak or two such as raise CAS one level, or voltage slightly.)
c) buy the optimal performance
d) find the validated memory list (though usually not an issue with name brands.. do note that occasionally BIOS updates add profiles. An older BIOS and newer memory for example may have no XMP options as the memory may not be recognized. Thus, the default settings are estimates and MAY even be unstable).

So, if I had to do this I'd get a 32GB kit (4x8GB), 2133MHz CAS9, then SELL the rest ($30-40?)
http://pcpartpicker.com/part/gskill-memory-f32133c9q32gxh

At $165USD though you'd really have to justify the cost, though I suspect you would rather buy an identical (same model anyway) kit as what you have now.

Approx $70- $100USD depending on model.

 

[Rajakrishnan]

If you want to add more RAM in the future, your best bet would be to try and buy another kit of the exact same RAM you just bought. If that's not possible, I'd try and find another 2x8 GB 1600 MHz kit with the same timings (CAS latency, etc). But even if you get an identical kit, it's not guaranteed to work.

Thanks for your valuable suggestion..

 

[Rajakrishnan]

Future upgrade?
Unless you edit video, or use some combination of software that benefits from more than 16GB then upgrading won't help.

But... to answer your question on that.

*In general:
a) don't mix memory (use same exact model number)
b) ideally buy as a single kit (a 2x8GB kit later of the exact same model number can actually be slightly different, though chances of failure are likely slim, and worst-case is likely just a manual tweak or two such as raise CAS one level, or voltage slightly.)
c) buy the optimal performance
d) find the validated memory list (though usually not an issue with name brands.. do note that occasionally BIOS updates add profiles. An older BIOS and newer memory for example may have no XMP options as the memory may not be recognized. Thus, the default settings are estimates and MAY even be unstable).

So, if I had to do this I'd get a 32GB kit (4x8GB), 2133MHz CAS9, then SELL the rest ($30-40?)
http://pcpartpicker.com/part/gskill-memory-f32133c9q32gxh

At $165USD though you'd really have to justify the cost, though I suspect you would rather buy an identical (same model anyway) kit as what you have now.

Approx $70- $100USD depending on model.

Thanks for your valuable suggestions and links..

 

[photonboy]

1)BIOS-> latest Asus Z97-A is "2801" (Nov 2015).

It just says "improve system stability"; I don't always recommend updating but I do any time they mention stability.

Can tell from CPU-Z, or in the BIOS somewhere.

2) Drivers-> http://www.intel.com/content/www/us/en/support/detect.html
If you care, I use the Intel driver tool. It can scan for any Intel driver updates though I suspect you won't find any.

3) Memory usage info:
Windows memory manager will tend to BUFFER the optimal amount of Windows and other program data. There's probably an algorithm that keeps track of how often you open certain programs, so if you do a COLD BOOT it may buffer at least 3GB right off the bat.

With 16GB installed, I often go above 6GB usage when Google Chrome is running with multiple pages open (where I compare sub-surface, dermal light scattering and differences in topology).

My dad's 2GB laptop (now using Windows 10 and an SSD) is pretty snappy and uses about 1GB with a few pages open in a browser.

*Anyway, my point is that Windows dynamically adds and removes data from memory so if usage seems high it doesn't necessarily mean you may need to add more in the future.

Very few games use more than 4GB (the game itself) of system memory. I'd be incredibly surprised if we saw any games use 8GB (again game only). Maybe a game like Star Citizen, or possibly if DX12 starts implementing tiled streaming (real-time streaming system to video memory such as zooming into a planet slowly).

Not sure if this helps or is useful. Anyway, I'm done. Cheers.

4) Samsung Magician's Rapid Cache-> this may or may not help in some cases (other than the benchmark). If you have a Samsung SSD or a different SSD with similar feature you might want to turn this on. I believe you read/write to the system memory then it's moved into the SSD.

It's meant I assume for when the SSD cache fills up, so it's just another cache. I can't tell if it helps, though it doesn't seem to hurt, nor does it appear to use much of my system memory (probably drops to zero when not needed).