We have Optiplex 780 mini-tower machines at work, and for the last couple of days want to upgrade them to the maximum memory possible. It's next to impossible to find an easy answer to what is the maximum memory is for these machines.
Dell specifications - http://support.dell.com/support/edocs/systems/op780/en/SM/SM_MT/specifications.htm - say it's 8GB DDR3 1066GHz
Two other documents on Dell website have 16GB as max memory.
Dell Optiplex 780 tech guide pdf (http://i.dell.com/sites/content/business/solutions/engineering-docs/en/Documents/optiplex-780-tech-g... - page 9, and Dell Optiplex 780 Setup and Features Guide pdf (http://support.dell.com/support/edocs/systems/op780/en/SFITS/SFITS_Al/SFITS_EN.pdf) - page 7
Anyone knows what's the correct information?
Size - 8GB or 16GB?
Which speed - 1066GHz or 1333GHz?
The MT will support up to 16 GB fine. Best bet is to get 2×(2×4 GB kits) from crucial for each machine. The part is here. Crucial memory is the best for Dell systems.
The link that mentioned the 8 GB only probably just meant the USFF and didn't list all the units seperately as the tech guide pdf does.
We tried upgrading to 16GB, using Mushkin memory: www.mushkin.com/.../993770.aspx , and the machine did not want to boot, it was bluescreening, and we even tried reinstalling Windows, and it did not work.
Why would Crucial memory work?
You were right, Philip, Optiplex 780 Mini-Tower accepts 16GB of DDR3, 1333Mhz.
Our problem was that 2 DIMM modules (out of 8) were defective. In all the discussion on what to do, we did not look at the diagnostics lights on the Mini-Tower case, to tell us what's wrong. Dell actually has a very helpful diagnostics document, <ADMIN NOTE: Broken link has been removed from this post by Dell> . We had lights 3 and 4 on, and from that we realized what's going on.
Thanks for your help Phillip, and I am marking your answer as helpful, since you confirmed that 16GB has to work. Once we knew that, we looked at other possible troubleshooting paths that led us to solving the problem.
Glad you got it resolved, I recommend crucial because it has always worked for me with Dell systems.
Most other users on these boards also prefer crucial as the Dells seem to prefer crucial RAM and there is usually less problems with crucial RAM.
We have found that other companies RAM does not always work as well or some of the modules are bad or alternatively only some of the modules work and some users reported that they can't boot if they have 4 modules (non-crucial) yet can if they use and 2 of the 4 modules only.
32 bit is limited at 4 GB of RAM.
If you install 16 GB of RAM on a 32 bit OS only 4 GB at maximum will be read.
You will need to upgrade the processor and switch the OS to 64 bit aswell as upgrade the RAM in order to upgrade to more than 4 GB.
Thats just corny. While "crucial" is a decent brand of memory its difficult to accept a recommendation based on "it always worked for me". Memory is a physical object and any brand can ultimately end up being defective. There are quite a few decent manufacturers of memory out there and I wouldn't go out there and buy crucial just because someone said they like the "ring" to the name or whatever. I've mixed 4 different brands in a single Dell system already and have had absolutely no problems as a result. That doesn't necessarily mean that I would go out and recommend using four different brands, because it seemed to work well that way. I could solder my own memory (and have) and use it just fine, so long as it was assembled with the machines specs in mind and done so in a careful manner. I just want to recommend to all of the other amateurs out there (no disrespect intended) that you don't have to go out and spend top dollar on "crucial" memory in order to upgrade your Dell. You can successfully upgrade your Dell computer with any brand of computer memory. Dell computers do not have a "discerning" pallet and It doesn't have to be a certain brand at all. Its simply nonsense for someone to recommend one brand over another. Memory compatability is a matter of physics, not opinion.
Its not just that its "always worked for me" but also many others on the Dell Community which have experienced boot issues with non-Crucial RAM with older systems especially the cheap "unknown" brands. You can look through the many other threads on the Dell Community Forums where Crucial is recommended after a user has tried this and the results with the Crucial memory have been fine and the cheap memory have lead to a booting issue or only half the RAM showing up etc. Certainly I won't recommend users to solder their own memory modules or attempt a cheap almost unknown brand.
As you said "Crucial" is a decent brand so why not recommend it? Crucial also has the advantage that it has a nice system scanner, lists compatibility for most systems and has a decent warranty if used for the said systems.
Personally I also use Offtek RAM on a regular basis depending on whats cheaper but I don't think this vendor is available outside Europe and for this reason I don't recommend it as a large majority of users are from the US/CA.
If you want you can also get the memory direct from Dell but this usually costs significantly more.