Gtx275 uses system ram but not HD4890 why?

vinshon

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Aug 30, 2009
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Hey guys after reading few threads about graphics card using up system ram, i still cant figure this out..

When i first put together my computer on XP32 bit, i have my full 3gb system ram with HIS HD4890(1gb ram).
My Computer displayed i had my full 3gb, but due to coil-noises i exchanged the HD4890 for a GTX275(896mb ram).
When i installed the GTX275 My Computer currently displays i have 2.7gb of ram. Why is that?
I dont know why my gtx275 with less ram would use up my system ram, i also tried reformating xp and even installing vista, the same thing happens.

ps. bios and cpu-z states i have 3gb of ram, but in windows and dxdiag it shows i have 2.7gb only
 
yeah i've read about hardware limitation but it doesnt indicate whats happening with my system... =(

3gb ram + 1gb video card = windows displays full 3gb system ram
3gb ram + 896mb video card = windows display 2.7gb system ram wtf 😵
 
before i took the 4890 out i had 3gb system ram, after i swapped it out and plugged in the gtx275 windows displayed i had 2.7gb, so i reformatted but still shows 2.7gb ram.
 


1) OP was having problems with coil noise on his 4890.

2) The OP exchanged it.

3) 32bit systems have a limitation, even if the memory is physically there only a maximum of 4GB maximum combined RAM and VRAM can be addressed.
 


1) I know

2) I know

3) Yes, I know 32bit systems have a limition, the system only only read 3-3.5gb of RAM. What I didn't know is you combine RAM and VRAM. So if I have 4GB RAM and 1GB VRAM on 32bit system, computer reads 3.25GB RAM, now what is happening, it can only take .75GB VRAM? Umm..

Can I get a few sources for this. I want to understand this combination theory more.