General: Worth a Try

This is going to sound crazy - but worth a try. Drop down to 2GB of system memory.

Also - does your card require power plugging into it? I've seen this sort of performance from cards that haven't got external power plugged in.

CB - But he's running Windows XP, which is 32-Bit. So 3-3.5GB is probably what it will detect. On top of that, there are limitations as to what a single program can allocate and detect. So you want to see what it says on the Windows System Properties screen and trust nothing else.

I'm not suggesting his RAM is borked, but I think it's worth trying with just 2GB, as some odd things might be happening

The 3-3.5GB limit was a physical one imposed by hardware issues, iirc - and didn't affect machines with registered ram.

I don't think 32bit OS's have the same limitation - I *think* they're limited to 4GB of addressable space - but I just don't know for sure!

Maybe a 64bit linux (live CD?) install running some benchmarks might help work out if the memory is at fault...

If it's a problem with XP getting it's knickers in a twist over memory allocation, then it might be time to switch to 64bit XP or (boo! hiss!) 64bit Vista...

I want to upgrade my machine with more ram soon, since photoshop slows down on my 10 megapixel images sometimes - another 2-4GB ram would be nice, methinks. So I'm actually thinking of swapping to Vista...

I promised myself I'd never do that, but maybe an nlite enhanced version of vista will be not rubbish. Maybe.

Just ran Call of Duty 4 again, still not getting anything above 25 frames per sec with only 2gb of ram. Really stuck for ideas?!

Just installing Half Life 2 Lost Coast to see if it is just a problem with COD4 that can't be helped.

This may be the wrong place to be asking, but I don't really want to have the dissatification of paying 60 pounds for Vista. If anyone has got any pointers, it'd be appreciated. (it may even resolve my problems)

Thanks for all the help so far,

Done a clean install of XP yesterday and it made no difference to anything graphically intensive. Call Of Duty/3dmark still gave poor performance which was a real let down after whiping alot of stuff off.

I'm beginning to think that it could be a memory issue, when I have the 2 x 2gb sticks in and check in the BIOS. Under hardware information it only says that 3009mb is installed, despite in cpu-z it says 4gb, I would of thought that if anywhere the BIOS would be correct. I'm stuck in a catch 22 now, I don't want to spend anymore money until I know it's definitely going to be sorted, so I'm reluctant to buy Vista incase it makes no difference at all. Unhappy days.

two 2gb sticks.

I'll test each 2gb stick independantly tonight when I get in from work.

Looking over my 3dmark06 Score again of: 4863 and comparing it to a few scores on Google. There appears to be nothing wrong. The majority of x1900xt are getting between 4200 and 5200 points in 3dmark06 which begs the question why am I having such ball ache playing Call of Duty if my graphics card isn't at fault. Half Life 2 seems to play faultlessly aswell.

Maybe I should just stop playing COD4, although I did buy this setup so I could play specifically that game. Bad times.

1.7, but I updated to that as soon as I installed the game. Not dual monitor and I even tried 7.6 drivers last nigth which are months old. Still no luck, so I guess it's time I packed in gaming, military life starts in a few weeks so it's probably for the best.

I just stuck 2 2GB OCZ sticks of DDR2 800 in my PC. I should have tested the speed of the thing before taking the generic 2x1GB sticks out...

Anyhow, I'm getting 3.5GB showing up in windoze. I guess that 3.5GB limit *does* apply to 32bit XP. I'll try running a live CD later and see what that says.

Scopse - have you tried running benchmarks off a live CD? A memory test on both platforms might be helpful...

Yuh-huh, you did, but there was some fuzziness in my mind as to where the 3-3.5GB limit was being imposed - by hardware (on 32bit machines, at least) or in software.

3.5GB is an odd limit for an OS to have. 4GB makes more sense to me...

Beanz - I have an Athlon 64. My memory limitations aren't hardware...

And Scopse has a Core2....

We're both on 64 bit systems, with 32bit OS's.

Scopse - the only time your graphics card takes memory away from the main system is when the graphics are on the motherboard. Yours aren't, so you should be seeing the same 3.5GB that I do. Even if your graphics were taking 512MB, you should still see 3.5GB in windows, because the 512MB your graphics card took would be the same 512MB that windows couldn't see anyway (in theory, in practice it depends on the way the memory is mapped and addressed by your northbridge. I don't have a northbridge, though - so maybe that's why I'm seeing 3.5GB and you're seeing less - *maybe*... I doubt it, but maybe... Maybe XP pro sees more than XP home?)

What does your post screen say about the amount of RAM you have? Have you tried going into your BIOS and disabling quick post (so it tests your ram every time you boot)? I would seriously consider downloading a 64bit live CD at this point, because 2.93GB of ram is a very, very weird amount of ram to have - it's not a "binary" number (a power of 2, I mean)... But then, neither is my 3.5GB.

CB - I don't think you've understood what Beanz and I are saying, and it's making for a confusing thread!

4GB is the overall limitation to memory allocation - for system memory, graphics memory - anything that has memory. So if you have a 512MB graphics card, you can only access 3.5GB of the system memory. That's why it shows 3.5GB.

Indeed. That is odd.

A confusing thread it may be, but there's nothing like confusion to clear one's thoughts to resolve the muddle and learn just a little more useful information. Now that is always beneficial.
2.93Gb, 3.00Gb, or 3.5Gb. I have a feeling Windows isn't capable of reporting the exact amount of RAM accurately. Indeed, I have had some strange readings from CPU-Z in the past, I suspect it's because it's still a Windows based programme.
Perhaps there's a better way of calculating real RAM totals. Then again, does it really matter that much?