Probook 6470b memory upgrade

[Alan248]

Hello, I currrently have 2 x 4GB memory modules (8GB total).  Would you please let me know if I will be able to swap out one of the 4GB with an 8GB, so I would have 12GB total - a 4BG and an 8GB?

Thanks!

[Huffer · Accepted solution]

Yes. From the manual:

Two customer-accessible/upgradable memory module slots DDR3-12800 (1600-MHz) dual channel support Supports 16384-MB of system RAM in the following configurations: ● 16384-MB (8192-MB×2) ● 8192-MB (8192-MB×1 or 4096×2)

Memory modules (PC3-12800, 1666-MHz, DDR3): 8-GB 670034-001

https://www.amazon.com/670034-001-Hewlett-Packard-1600Mhz-Pc3-12800-Sodimm/dp/B00J2K7U84/ref=sr_1_4?...

The manual does not list a 12 gig configuration (4 + 😎 probably because it is not that good of an idea. You lose dual channel operation. For many computer users 8 gigs (4 + 4) in dual channel will outperform 12 gigs (4 + 😎 in single channel. 8 gigs is plenty of memory for almost all users and if you need more you ought to invest in 8 + 8 = 16 to keep it dual channel. But 4 + 8 will work. 

Download Service manual here

Post back with any more questions and please accept as solution if this is the answer you needed. 

[Alan248]

Thank you very much Huffer!!

I found this also... which is what you have stated.  I guess I can try it before buy 2 8GB, thanks again!

You can, but your RAM will not run “dual channel” (if the two modules don’t match).
Intel’s 4th Gen. memory controllers can default to single channel mode, though. This means that the RAM speed will take a performance hit (since it will not be splitting the data in two and writing to both sticks simultaneously any more), but RAM speed doesn’t have a huge bearing on the overall speed of a laptop anyway. You may find that the additional amount of memory allows Windows to access its page file less often — (i.e. swap RAM contents on to or off of the hard drive) — making more of a difference than the single channel (vs. dual channel) read/write speed does.

[Huffer]

This is true. If you are accessing the virtual memory (page or swap file) regularly with 8 gigs then having 12 gigs will improve performance. The gain from running in "real" memory vs. "virtual" memory is enormous while the gain from dual channel is subtle, at best. Memory speed goes up 7 or 8% with dual channel meaning overall performance might go up 2 or 3%. Most people just do not use more than 8 gigs, however so adding more memory for them does nothing while losing dual channel means their performance will take a small hit. 

[Alan248]

Thanks again, Huffer!!