T60 w/X1400 GPU but reported having 512 MB VRAM?!

[Johan]

I just came across this T60 on eBay which is stated to be a 2623-D3U which, according to Lenovo's specifications (also in the ltwbook on page 147/283) has an ATI X1400 GPU with 128 MB VRAM. However, on one of the images shown in the eBay listing, which is a screen-dump from Windows XP display properties (the "Adapter" tab), the video-memory is reported to be 512 MB?! Can anybody explain this??

Johan

[dr_st]

All video cards of recent generations can also share system RAM. Sometimes the adapter properties show the total addressable RAM, not just the GPU RAM.

My 2623-D3U shows the same.

[GACrabill]

I just came across this T60 on eBay which is stated to be a 2623-D3U which, according to Lenovo's specifications (also in the ltwbook on page 147/283) has an ATI X1400 GPU with 128 MB VRAM. However, on one of the images shown in the eBay listing, which is a screen-dump from Windows XP display properties (the "Adapter" tab), the video-memory is reported to be 512 MB?! Can anybody explain this??

I can't explain it but I have a T60 2007-CTO which shows the same 512MB VRAM (Belarc shows it as a 2007-V3B). I bought mine from the same seller (I won't buy from him again, serial number cut from bottom and it came with a 2GB stick of PC-4200 instead of PC-5300 memory). It shows 512MB VRAM with either 3GB or 4GB of RAM installed .... I did not check to see if a different value showed if only 1GB of RAM was installed.

[Marin85]

Your X1400 comes with 128 MB dedicated video memory. The difference up to 512 MB comes from the system memory (ATI Hypermemory), i.e. it´s shared by the graphics card. The latter uses the shared memory if it´s own buffer becomes insufficient to accomplish a given task. The amount of Hypermemory is determined by the card model and the installed driver. In the case of X1400 the max shared memory is 384 MB (with the newer drivers, XP SP3 and Vista for sure, probably XP SP2 as well). So, what is reported under video memory is not the dedicated one but the total memory available to the gpu.

Marin

[Johan]

Thanks very much, all of you, for sharing this insight and hence (once more!) contributing so very valuable to my continued ThinkPad-education! As obvious, I didn't know about shared memory in dedicated (discrete) GPU's; I had only heard about it in association with integrated GPU's. Perhaps it has something to do with that I have very relaxed graphical demands... e.g. I never played a game, so if I only have 8 or 16 MB VRAM, I am entirely happy!

Thanks, again!

Johan

[crazyfrog]

BTW, XP only reports the total available graphics memory. Vista will tell you exactly how much is the dedicated video memory and how much is the shared system memory.

In my case, ATI V5250 has 256MB dedicated video memory and 1279MB shared system memory reported by Vista. That is a total of 1535MB available graphics memory.

[Marin85]

In my case, ATI V5250 has 256MB dedicated video memory and 1279MB shared system memory reported by Vista. That is a total of 1535MB available graphics memory.

I know, I know I bet you are using modded drivers (I believe with the latest desktop drivers ATI/AMD have increased the Hypermemory from 768 MB to 1279 MB for the the FireGl 5200).

Cheers

Marin