Virtualization with Win7: insufficient memory?

Question

I've been using virtualization (VirtualBox and VMWare Player) for years on my Lenovo T410 with WinXP and 3GB RAM
After I've upgrade to Win7 64bit with 5GB ram this is no more working (virtualization is enabled in the BIOS of course).
After few seconds, they both (VirtualBox and VMWare Player) report insufficient memory in the host, while instead there is a lot "available", as reported by the task manger.
VMs are configured with 512MB RAM and when I start them there are 3GB "available" in the host.
Of course there is a lot of people successfully running virtualization in Win7, but looking for similar issues in the web, I found one same case (in 2011) with VMWare on Lenovo T410 with Win7, and that post reported a possible bug of Win7 on Multi core architectures with UNMA memory management.
Have you got any hint?
Thanks a lot in advance
ViSco

Answer 1

Please let me recap:
- I'm running just one  VM at a time, first I try VirtualBox, then VMWare, both report insuffucient physical memory
- From the resource monitor a lot of memory is "available" (3GB), I don't see the need to obtain still more
- before with PC Lenovo T410, WinXP, 3GB RAM, bot VirtualBox and VMWare could run with good performances
- now with the same PC, Win7 and 5GB they both cannot run anymore (one at a time)
- I've this kind of issue only with virtualizators, no other application has ever reported insufficient memory
I'd conclude the issue stands in the combination virtualizator/Win7/Lenovo T410.
Useful to know: anywhone in ths forum can run this combination? WIth which amount of physical and available memory?
Let me also remind I found one case in a Win7 forum about exactly this combination not working (wtih 8GB RAM!)
That old post (in 2011...) reported some issue in Win7 managing PC multi-core archtecture with UNMA memory management: is it the case for T410?
Here an hypothesis: if UNMA partitions the physical RAM to the different cores (I see 4 "CPU" in the task manager) and if Win7 is not able (while XP was!!) to manage them flexibly enough, than the effective availability of memory for the single process is strongly reduced by a 4 factor, with respect to the one reported by the task manager or resource monitor.
And furthermore, my unbalanced RAM configuration with an odd number of GB (5GB) could make it for Wn7 still more difficult to assign the available memory to the CPUs(but in the WIn7 forum, the post was about VMWare/Win7/T410 not working with 8GB).
In conclusion, I'd really appreciate:
- as many people as possible to answer to my question above
- any suggestion that could improve the memory assignment policy in this configuration
Thanks in advance to all