As for the number that is listed in the prod. spec., I am not sure what exactly it refers to. It might be true that the 4GB is only the soft upper limit of the driver, where there's a hardware limit in the iGPU as well (which would be the bottleneck). But honestly I don't really know how it works (across different OSes).
]]>You can't expect an integrated GPU to run demanding games at the same speed as a discrete card of the same vintage, I'd say that 20fps is already good. You have to remember that the gpu is using the system's ram, which is slower than the dedicated vram in discrete cards.
Now if you had an iris or iris pro gpu that would be a different matter. Those are starting to get interesting and I'm curious to see what intel gpus can do tow or three generations from now. That said, I do have an HD Graphics 520 and I'm quite happy with it, but I don't really play games (but I did test a few just out of curiosity about the speeds I would get and to check everything was working as intended).
]]>However I don't really have any source document on hand, so just take it as a hearsay and do further research if desired.
]]>[viktor@desolve-nettop ~]$ lspci -v -s 00:02.0
00:02.0 VGA compatible controller: Intel Corporation HD Graphics 530 (rev 06) (prog-if 00 [VGA controller])
Subsystem: Intel Corporation HD Graphics 530
Flags: bus master, fast devsel, latency 0, IRQ 125
Memory at de000000 (64-bit, non-prefetchable) [size=16M]
Memory at c0000000 (64-bit, prefetchable) [size=256M]
I/O ports at f000 [size=64]
[virtual] Expansion ROM at 000c0000 [disabled] [size=128K]
Capabilities: <access denied>
Kernel driver in use: i915
Kernel modules: i915
while in dmesg I see:
[viktor@desolve-nettop ~]$ sudo dmesg | grep drm
[ 0.705255] [drm] Memory usable by graphics device = 4096M
[ 0.705257] fb: switching to inteldrmfb from EFI VGA
[ 0.705363] [drm] Replacing VGA console driver
[ 0.711543] [drm] Supports vblank timestamp caching Rev 2 (21.10.2013).
[ 0.711544] [drm] Driver supports precise vblank timestamp query.
[ 0.718594] [drm] Finished loading DMC firmware i915/skl_dmc_ver1_26.bin (v1.26)
[ 0.719838] [drm] GuC firmware load skipped
[ 0.720305] [drm] Initialized i915 1.6.0 20170123 for 0000:00:02.0 on minor 0
[ 0.722654] [drm] Initialized i915 1.6.0 20170123 for 0000:00:02.0 on minor 0
[ 0.764336] fbcon: inteldrmfb (fb0) is primary device
[ 0.851473] i915 0000:00:02.0: fb0: inteldrmfb frame buffer device
[ 2.346105] [drm] RC6 on
[21034.284297] i8042 serio i915 video button i2c_algo_bit drm_kms_helper syscopyarea sysfillrect sysimgblt fb_sys_fops drm intel_agp intel_gtt
So, theoretically my IGPU can use up to 4 Gb of my RAM (8 GB total on board), but lspci says that only 256 Mb is available. VideoRam option in xorg.conf for intel driver seems to be deprecated. So I wonder if there any ways to increase dedicated GPU RAM or directly use Intel DVMT? As for now it seems like DVMT is not working - when I launch some graphics-heavy application (e. g. Bioshock Infinite @ steam) I see the same 256 Mb of dedicated GPU RAM in lspci output.
Is there any ways to increase dedicated GPU RAM at kernel or xorg level? Or can I enable Intel DVMT not using UEFI?
Thank you
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