VM allocations errors on startup are random, they appear only when the ram address that the emulator tries to use is already taken up.
The amount of ram you have is irrelevant, if that address is occupied, the emulator will not start.

The only way you can try to fix it is by restarting your pc,and starting up the vm build immedietaly after. That way you have a better chance of having that address still available.

That, and reduce the number of programs you load on startup. There are no other solutions and there is nothing we can do with the current vm implementation.

And it's precisely this kind of problems that made us decide we will remove the Vm version as soon as the vtlb is better implemented.

And about vista, I use vista and it works perfectly. It's all about how many and which programs you have on load on statup.

Additionally, programs like Skype, Yahoo Messenger, and the Sun Java VM are notoriously bad about sucking up gobs and gobs of virtual memory. So if you're running one of those two first apps, or apps that use Java, then.. well.. don't.

So, in other words the newer SVN releases are attempting to allocate virtual memory addresses that the 395 release doesn't. That makes sense. Seems kind of hack-ish to have to try and close programs to get it to run, but admittedly i know very little about memory allocation. It was my understanding that it's mostly done through the OS.

395 is working beautifully for me, i just wanted to try the SVN to see if it would run any faster ^^

Disclaimer:
I don't want to seem like i'm I'm complaining - i'm not. Especially since PCSX2 is free of cost. I really love the PCSX2 project and i admire all the hard work you people put into it.

I intend to donate to the project when i get some extra cash.

Keep up the good work though and lets hope the TLB version really improves in the future

Since this seems to have caused several threads already:

Remember that also Pcsx2 takes up virtual memory when you're testing. If a SVN beta doesn't run, make sure you didn't run another version of Pcsx2 before it or that might be the cause, especially if a previous pcsx2 instance crashed. Reboot before switching between vm builds!