Is there a way to check the size of the video memory? Specifically, is there one that works accurately for both integrated GPU's as well as PCI/AGP graphics cards?
Many integrated GPU's have dynamically allocated memory, so the solution would hopefully return either the maximum available video memory or the currently allocated amount. For stand-alone NVidia or ATI cards it would obviously return the total amount of physical GPU RAM.
lspci -v does output memory figures, but I do not believe it is the video memory. I suspect the figure reported is some system memory allocation or block or channel size, but I don't know for sure. You can see in these test results that lspci was wrong in 5 of the 6 tests:
** ASUS EN210 PCIe - 1024 Mb ***
01:00.0 VGA compatible controller: nVidia Corporation GT218 [GeForce 210] (rev a2)
Subsystem: ASUSTeK Computer Inc. Device 8354
Memory at e3000000 (32-bit, non-prefetchable) [size=16M]
Memory at d0000000 (64-bit, prefetchable) [size=256M]
Memory at e0000000 (64-bit, prefetchable) [size=32M]
*** Galaxy 8400GS PCIe - 512 Mb ***
01:00.0 VGA compatible controller: nVidia Corporation G98 [GeForce 8400 GS] (rev a1)
Subsystem: nVidia Corporation Device 05cc
Region 0: Memory at e4000000 (32-bit, non-prefetchable) [size=16M]
Region 1: Memory at d0000000 (64-bit, prefetchable) [size=256M]
Region 3: Memory at e2000000 (64-bit, non-prefetchable) [size=32M]
*** VirtualBox VM - 10 Mb (headless server) ***
00:02.0 VGA compatible controller: InnoTek Systemberatung GmbH VirtualBox Graphics Adapter
Memory at e0000000 (32-bit, prefetchable) [size=16M]
*** VirtualBox VM - 128 Mb ***
00:02.0 VGA compatible controller: InnoTek Systemberatung GmbH VirtualBox Graphics Adapter (prog-if 00 [VGA Controller])
Memory at e0000000 (32-bit, prefetchable) [size=128M]
*** S3 Savage 4 AGP - unknown Mb (old lspci log), but I don't think they made these cards with 128Mb memory! ***
00:01.0 VGA compatible controller: S3 Inc. Savage 4 (rev 06) (prog-if 00 [VGA controller])
Subsystem: IBM Unknown device 01c5
Region 0: Memory at feb80000 (32-bit, non-prefetchable) [size=512K]
Region 1: Memory at f0000000 (32-bit, prefetchable) [size=128M]
*** NVIDIA Quadro FX 1800 integrated - 1024 Mb ***
01:00.0 VGA compatible controller: nVidia Corporation GT215 [Quadro FX 1800M] (rev a2) (prog-if 00 [VGA controller])
Subsystem: Dell Device 040c
Memory at e2000000 (32-bit, non-prefetchable) [size=16M]
Memory at d0000000 (64-bit, prefetchable) [size=256M]
Memory at e0000000 (64-bit, prefetchable) [size=32M]
Best Answer
This is the o/p of dmesg with a ATI 6370HD discrete 1G graphics card. "Detected VRAM RAM=1024M, BAR=256M", check for this line.