Nvidia TurboCache Increase

[L E Jay]

Been looking into options of improving the memory on my laptop. (Acer aspire 9301) with a geforce go 6100.

The card has 256mb dedicated and with Turbocache it has 356mb. I am looking to improve on this and get it up to 512mb.

Now I've read most things about the turbocache etc, but no-one seems to know how to increase the amount the gfx card can use. On a low/medium laptop using the system ram can improve things and you can't just chuck it out and buy another card.

Anyway, I wonder if this is driver controlled and is it likely to be contained in the driver .inf file. For example my gfx card will take up to 128mb from ram, the .inf file has references to MaximumDeviceMemoryConfiguration in each section.

Would it be feasible that an adjustment of this number would increase the amount of ram the Turbocache would use? Or am I clutching at straws?? As

[coolcop06]

well honestly i dunno if there is a way to forcefully increase your turbo cache... or if it would really make a difference..

but what i do know is, the more RAM you put in your computer, the bigger turbocache you have. so if you REALLY want the turbo cache to be bigger, kill two birds with one stone and buy more RAM. :)

[Nautis1100]

Anyway, I wonder if this is driver controlled and is it likely to be contained in the driver .inf file. For example my gfx card will take up to 128mb from ram, the .inf file has references to MaximumDeviceMemoryConfiguration in each section.

Would it be feasible that an adjustment of this number would increase the amount of ram the Turbocache would use? Or am I clutching at straws?? As

Clutching at straws when it comes to the INF.

From Microsoft:

MaximumDeviceMemoryConfiguration=n

Specifies the maximum number of megabytes of device memory that the miniport driver will attempt to map into the system address space for one video device enumerated by PCI. Windows uses this value as a hint to determine how many system page table entries (PTEs) it should allocate for the mapping. For this entry to take effect, a reboot may be needed. You can determine whether a reboot is necessary by checking the status of your device in the Device Manager.

MaximumNumberOfDevices=n

Specifies how many video devices (as enumerated by PCI and driven by your miniport driver) are expected to be present in the system. If you specify this entry, you must also specify the MaximumDeviceMemoryConfiguration entry. For this entry to take effect, a reboot may be needed. You can determine whether a reboot is necessary by checking the status of your device in the Device Manager.

For more technical information on TurboCache I suggest reading NVIDIAs Technical Brief (PDF). Also the "How Does It Work?" and "Key Features..." sections here.

[L E Jay]

Coolcop you are probably basically correct.

Nautis, thanks for the articles. Turbocache is a very perculiar thing.

Rather than Turbocache enabling more system memory to be used by the graphics card, according to the flow diagram (Pg 5) It simply allows the ram that is used (normally as with any graphics cards) to be reassigned to system memory quicker than normal. It transfers at 4gb/s which they say has a net effect of 10gbs which is faster.

What its not saying is exactly how much can be used by the graphics card... (Technically as much as a grfx card can normally use from system memory) which is what I wanted to increase, because the figure that they give out is how much can be managed in by the Turbocache manager and sent back to system memory but faster.

The extra amount used by your gfx card which they add onto it is in fact what can be used in a hurry by system memory but not by the graphics card. Nevertheless the recyclement of memory in this manner means that what is used by the graphics card and sent back to memory can be used quicker again by the gfx card itself. So once you have gone round in a big circle, you find that the memory usage by the gfx card from the system is faster than normal. (They are inferring it to be equal to the ram onboard the card and therefore place the figure as onboard gfx + what can be used by the gfx card.

The initial use of system ram is probably the same as a non turbocached card... After that its of some use.

What defines the amount of turbocachable memory I'm not sure, mine is 128, I would like 256, but if I increased ram quite frankly I should be able to use maybe even 1g. This would have some effect on gaming, although everything else on the card will hold it back.

To prevent system memory using its own 128mb, system ram needs enough of its own. As coolcop says 'buy more ram' However if you prevent it from doing this juggling act, where gfx card needs it one minute, the system needs it the other but there is enough that memory is never in shortage, then surely turbocaching the memory isn't necessary, although (I don't know enough about ram) RANDOM surely means that you can never prevent it from accessing memory in this fashion. But surely it uses the empty slots first.

I'm not sure it really does anything useful anymore, i.e. it is limited if you increase enough system memory. Its not required.

(Actually a 64 system with a faster transfer of information to ram with enough of it would in some sense mean that no onboard dedicated ram is required for the gfx... a bit odd. IG is supposed to be pants, but I suppose often its not enough and it isn't fast enough).

The 128 value, would be interesting to adjust but if you stick in 4gb ram , you probably have enough for system and gaming, where turbocaching is no longer require. Quite literally, there is a memory value used by you computer at excess load, that beyond which Turbocache no longer has any effect. So really it is best for low system ram computers, unless on high system ram computers, the gfx (which has its fixed ram limit- oh why didn't I buy a laptop with a decent gfx card- there's probably 1000's of people that say that, so no small matter) actually interferes with system memory that is in effect, during its random usage...

They really are trying to say that system ram is as quick as onboard dedicated ram though.

Nevertheless they probably set it up so half in half out, so that the turbocache amount is half of what can go into memory. 256 means that only 128 can be Turbocached. Something like that.

This whole speed issue makes Ready Boost interesting. If Turbocache speeds up the function of memory, then a sd card ain't gonna be useful for gfx memory, but then it wouldn't anyway. In theory an SD card won't add to your gaming, but could system memory use a £6 4gb SD and never require the ram back from gfx and not slow things down. Yes it would be slower, but it might be enough and fast enough for system.

So I have 1gb ram and a 256mb +128TC card. I can wack in 4gb of ram for surfing, but how much quick ram do I need if I only need ram for the system when its being used by the gfx card. Its all about allocation rather than speed when you have the volume unless you are going to tell me that the system can slow the graphics down by using slow ram of its own...

There's probably a massive amount of people with the Turbocache and using it due to pushing their pcs at bit futher, but its a fine middle line to get the highest performance. Best guess is that its more ram, but 'enough' after which you ain't improving anything with Turbocache. Maybe 4bg is enough, slightly too much, for a useable Turbocache, whereas beyond that you seriously needed a better gfx card. No question.