Thinkpads Forum

Say I have a LCD that I want to run at 1600x1200. Would that be possible? Running Windows 95 and through the docks VGA slot.

Definitely not 1600x1200. I can't find documentation right now to verify what the actual maximum resolution on an external monitor is for the 760. I'd guess it was only 1024x768 or maybe 1280x1024...You can probably find out what the max resolution is just by plugging it in and trying to increase the resolution as high as it will go.

[Added later:
According to twbook.pdf, the 760L and 760XL had a Trident CYBER9320 video card with 1 MB DRAM, which could drive an external monitor at "1024 x 768 w/ 256 colors up to 75 Hz".]

Phil.

Well, I thought all the 76x series had the same video card, but I have a 765D which apparently has a 2mb card. I gather not 1600x200, but do you think I could get to 1400x1050? If not thats fine, I doubt I'll hook it up to the screen anyway, was just curious.

Found this PDF via Google:
http://sysdoc.doors.ch/IBM/TH760.PDF

765D/L: Trident CYBER9385 /64-bit SVGA accelerator / 2MB EDO
DRAM / 70ns / PCI 2.1 / 32-bit/ DCI, Direct Draw, EnDIVE support /
External SVGA to 1280 x 1024 w/ 256 colors or 1024 x 768 w/ 65,536
colors

So 1280x1024 is the max, and at that resolution, you can only output in 256 colors.

Though it is sometimes possible that you can achieve better resolutions than the IBM specs if you are using Linux and using a non-IBM driver. But that is all hypothetical. And I'm guessing you're using Windows.

Phil.

i-SnipeZ wrote:I have a 765D which apparently has a 2mb card. I gather not 1600x200, but do you think I could get to 1400x1050?

I had an i Series 1124 Thinkpad until very recently. That laptop had a 4MB video card and could support only up to 16-bit 1280x1024 through the VGA port, no matter how hard I tinkered with the registry. I am 200% sure your 765D's 2MB card cannot output 1400x1050.

Resolution and color depth have a direct relationship to the amount of video memory that is needed. Assuming only standard 2D video requirements, take the pixel dimensions and multiply them together; 1280 x 1024 = 1,310,720. This would be the number of bytes of video memory required to drive the display at 256 colors. Increasing the color depth essentially means that more bytes would be needed. 256 color is 8 bits (or 1 byte). 64K or 65,536 colors is 16 bits (2 bytes) so you need 2,621,440 (1,310,720 x 2) bytes of video memory for that combination of display size and color resolution. That exceeds the 2MB of EDO video DRAM that the 765D has.

However, given that if the graphics chip supports these higher resolutions and you use a driver that takes advantage of them, 2MB is enough to generate 1400 x 1050 at 256 colors (1,470,000 bytes) and even 1600 x 1200 at 256 colors (1,920,000 bytes).

ref: http://www.pcguide.com/ref/video/modesBuffer-c.html
ref: http://www.pcmech.com/article/video-memory/

Interesting. Well, its running Windows 95. Either way, cool to know. Again, I doubt I'll hook it to my monitor anyway, the only reason I'd want to anyway is to get a little more viewing area in Sim City 2000.

From the "Thinkpad 760XD/760XL/765D/765L Technical Reference" Link: http://conradshome.com/thinkpad/765tref.pdf ...

There is a video modes chart a ways down the pdf... http://conradshome.com/thinkpad/760vidmode.png

Looks like supported is: 1280x1024@60Hz in either 16 or 256 colors to an external monitor with 2MB of VRAM