My Computer overheats, and then freezes up.

[naut]

Ok. Here's the solution. Your laptop runs XP or Vista yes? That means it is not optimised to run more than 2GB of RAM/Virtual Memory. What's happening is the games are maxing out your memory and trying to constantly manage the paging of your RAM to Virtual Memory, causing it to over-work and over-heat. Which in-turn causes your PC to shut itself down so as to avoid internal damage. Simple solution:

Part 1:
1. Download and install Explorer Suite CFF Explorer
2. Run it
3. Click open and find the .exe file related to your game
4. A screen will appear with a list of headings down the left side, click "File Header"
5. On the right a bunch of values will appear, look for the row "Characteristics" and press the "click here" box
6. A window will appear with a bunch of tick boxes, look for the one "App can handle >2gb address space" and tick it, click 'ok'
7. Save and close

Part 2:
1. Go to command prompt
2. Type: BCDEDIT /set IncreaseUserVA 3072, click enter
3. Close

And you'll be good to go.

[Prussian to the Iron]

thanks all, but i finally got a Rolodex Laptop Stand, which sits it up quite high. though i may soon cut out the metal mesh, which seems to just keep the heat right there, but leave the structurally important metal strips to hold it up.

[ICantSpellDawg]

If it is a compaq, they are notorious for having processor heat-sink problems. I bought one for my fiance and a the heatsink came lose. The cooling tray might help, but with a heatsink issue the only real option is to re-attach it.

[Xiahou]

Ok. Here's the solution. Your laptop runs XP or Vista yes? That means it is not optimised to run more than 2GB of RAM/Virtual Memory. What's happening is the games are maxing out your memory and trying to constantly manage the paging of your RAM to Virtual Memory, causing it to over-work and over-heat. Which in-turn causes your PC to shut itself down so as to avoid internal damage. Simple solution:

Part 1:
1. Download and install Explorer Suite CFF Explorer
2. Run it
3. Click open and find the .exe file related to your game
4. A screen will appear with a list of headings down the left side, click "File Header"
5. On the right a bunch of values will appear, look for the row "Characteristics" and press the "click here" box
6. A window will appear with a bunch of tick boxes, look for the one "App can handle >2gb address space" and tick it, click 'ok'
7. Save and close

Part 2:
1. Go to command prompt
2. Type: BCDEDIT /set IncreaseUserVA 3072, click enter
3. Close

And you'll be good to go.

A couple points...
-Telling the OS that an App can address more than 2GB of memory doesn't make it true.

-Making 3GBs of RAM addressable in a 32bit OS means that you're stealing memory addresses that are reserved by the kernel. If a device driver is expecting that space to be available and it isnt, you could be in for some serious stability issues. You may get away with it, but you should at least be aware of the possibility.

The real solution to the 2GB memory limit is a 64bit OS. Even still, if you're running 32bit games, they're not likely to see more than 2GB of RAM regardless.

[Tellos Athenaios]

Couple of points 2:

These tricks are about virtual memory, i.e you are not actually tricking the OS into believing that there is more real memory. To put this into perspective; in a 64GB OS the amount of virtual memory the system can work with is 2^64 bytes however I don't think that there is actually a single laptop with that much memory on the market right now. And anyway the memory management of the NT kernel should be quite capable to handle apps that allocate more than 2GB of RAM even if there's only 2GB available: the concept is known as swap.

Part two is that the OS would trigger an OOM error in userspace before it would accept a memory shortage in kernel space. And by the time a system with 2GB memory manages to run out of memory for the kernel you have bigger problems to worry about.

That said, if you are not actually running with more than 3GB RAM and therefore if you are not actually running with a 64bit OS and at least 4GB of RAM this whole thing is pointless. And when you do have a 64bit OS and 3GB of RAM or more the second part which sets the amount of available virtual memory is counter-productive.

[Xiahou]

And anyway the memory management of the NT kernel should be quite capable to handle apps that allocate more than 2GB of RAM even if there's only 2GB available: the concept is known as swap.

Are you sure about this? Non-large address aware 32-bit apps are only assigned 2GB of address space. Swapping occurs if the amount of memory demanded from all applications (and OS ect) exceeds physical RAM available.

Part two is that the OS would trigger an OOM error in userspace before it would accept a memory shortage in kernel space. And by the time a system with 2GB memory manages to run out of memory for the kernel you have bigger problems to worry about.

I think the problem is if a device driver expects a certain memory address within the 2GB space to be available and attempts to utilize it- then you're headed for system instability.

Frankly, Microsoft recommends against this sort of tinkering in all but a handful of situations involving servers. For end users, I don't really think that the theoretical gains are worth the trouble.

[Tellos Athenaios]

As a general rule of thumb device drivers get loaded before any heavy user space application; and those drivers (e.g. for PnP devices) that do get loaded on demand cannot make assumptions about addresses being available or not by their definition anyway. Furthermore allocation of memory (malloc) returns a pointer to the block allocated by the OS, or NULL on failure. At that point (malloc returning NULL) for most applications there is pretty much nothing that they can do but roll over and die.

If you allocate and use an additional 2.5GB of memory in a system with 2GB physical memory where before the load was 1.5GB of memory and you have an additional 4GB swap file... the sum is 1.5 +2.5 = 4GB in all address space used. Of course you are going to see a lot of trashing and the system will more or less freeze up. So things might continue running or you might get an OOM error which kills the process that attempts to fill an additional 2.5GB of RAM.

But consider if the load had been only 0.5GB: the math works out as 3GB of load and things should continue running normally albeit slowly because of trashing. Things get even more complex and opaque when the system uses “overcommitting” (don't know if NT does that).

[Husar]

The real solution to the 2GB memory limit is a 64bit OS. Even still, if you're running 32bit games, they're not likely to see more than 2GB of RAM regardless.

So where do I get 64bit copies of all my games?
And does it really matter if the games were designed in 32bit with the 2GB limit in mind?

[Xiahou]

So where do I get 64bit copies of all my games?
And does it really matter if the games were designed in 32bit with the 2GB limit in mind?

Well, you don't necessarily need a 64bit app to benefit from a 64bit OS. If a 32bit app is large address aware, it can use up to 4GB of RAM in a 64bit OS. Under a 32bit OS the maximum large address aware app can utilize is 3GB- and that's only if you do the unsupported boot hacks that were discussed above.

Some games are starting to offer 64-bit versions though. Elemental, for one, is supposed to make a 64bit version available sometime after the game's initial release. The size of the game world is supposedly only limited by memory, and in Win7 64bit it could theoretically have up to 8TB allocated. (although Win7 itself "only" supports 192GB of physical RAM, so I guess 8TB would involve massive swapping... here's a handy chart.).

[Subotan]

*Interrupts Conversation*

So, say, if I was purchasing a laptop with 4GB of RAM, I would need a 64 bit OS to utilise it's full capacity, right? But if most games/applications as you say don't have 64 bit versions, what's the point of getting a 64 bit OS, or even more than 2GB of RAM?

[Tellos Athenaios]

Speed & security. Speed because the 64bit OS (built for AMD 64 instruction set) can work with 64bit registers and assume more advanced uses for SIMD; security because the CPUs that run it offer things like killbits on memory which is used by the CPU to prevent execution of arbitrary data -- and these features are by and large inaccessible to a 32bit OS.

[Xiahou]

*Interrupts Conversation*

So, say, if I was purchasing a laptop with 4GB of RAM, I would need a 64 bit OS to utilise it's full capacity, right?

To get the full capacity, yes. You'd likely see around 3GB and change available.

But if most games/applications as you say don't have 64 bit versions, what's the point of getting a 64 bit OS, or even more than 2GB of RAM?

In short, because you could have multiple applications running- each using up to 2GB.

[Subotan]

Ah OK, thanks