screen resolution

[grace]

I have a sis 650_651_M650_M652_740 display adaptor and a HP M50 pavilion monitor. In settings/advanced list all modes, it lists display modes up to 2048 by 1536 at 75 hertz but the maximum display I can get is 1024 by 768 at 60 hertz although the resolution settings bar goes up to 2048. When I try and set it to a higher resolution the screen goes blank and "self diagnosis -pc display settings correct" message comes up in green writing. When I uninstall the display adaptor driver and device manager lists it as vga compatible, I can get 1600 by 1200 but my sons 3d games won't play with the message "no 3d device detected".
I bought this computer and monitor together secondhand with windows 95 on it. It could run many games that are just a black screen now and attain the highest resolution. I have had this problem since I got rid of windows 95 and have since had windows 98, then windows 2000, now windows xp.
I am currently running the monitor as default monitor, although running it as hp pavilion or plug and play doesn't make any difference. If I had never seen it perform so well when win95 was on it, I wouldn't be spending hours and hours trying to solve this problem since last september.
This is the first time I have posted on a public forum to ask for help because I am all out of ideas. I have tried all kinds of solutions and hardware troubleshooting problems, according to all, I should be able to get much higher resolution. any help greatly appreciated
Sincerely, Grace

[bluemoon]

http://www.hp.com/cposupport/manual_set/bph07336.pdf

Look under chapter 5.0

Looks like that's all your monitor will support.

They also say that setting resolution higher than supported can damage your monitor.So,be careful.

[Baddog]

What are your system specs and welcome to Sysopt.:t

[grace]

Thankyou for your replies
bluemoon: yes I read that 1024 by 768 is the highest supported resolution for this monitor....doesn't explain why it worked so well under win95 though
Baddog: thankyou for your welcome :) . This is an elitegroups socketA K7SOM+ mainboard with onboard sound and graphics 384mb ram and an amd duron 900 processer.

[bluemoon]

Not sure why it works better in win95.My wild guess is under win95,the onboard agp video chip is not working properly in a way that the cpu / memory resources are not hogged that much.??

Although 384 mb ram should be good enough for win2k,it is a lot for running win95.So,you have some advantage there.

Other thing I can suggest is to make sure your bios is up to date and motherborad driver is installed properly for win2k.Also,you can try different bios settings on agp memory sharing and so forth.

[xenomorph69]

that HP you have is a Walmart Bundle right?

the monitor will only support the 1024 X 768 at 60 - 70 hz

that is as high as she will go