After the machine has stood for several minutes with no action and gone to energy saving mode (dark screen), pressing any key brings up the message: 'Internal stacks overflow, system halted.' and the machine locks up. Revival necessitates switching off manually, without the opportunity to close down Windows, then re-booting from scratch. My config.sys file includes the line: Stacks=9,256. Ought I to amend this and, if so, how should I assess what values would be best? No modifications have been done recently with which this problem might have been associated. No lasting harm has been done on these occasions; it's just been irritating. Thank you for any assistance. Kind regards, J.G

I don't think changing your config.sys statement will help. Now days programs alocate their own stack. I changed mine to read "stacks=0,0" years ago and have never had a problem. Hopefully someone here is familiar with the IBM and energy saving mode. Grasping as straws, do you have something like a screen saver trying to run when it enters suspend mode?

J, Think back, something has to have changed. If it used to work with stacks at 9,256 then it still should. A hardware failure is possible, but look at the obvious first. Have you got something plugged in the USB port? Have you added some new hardware or software? If you really want to increase the stack size, try stacks=12,256 or heaven forbid, stacks=12,512 Keep in mind that the larger the stacks, the less memory for your programs. But again, if it used to work with stacks=9,256 and now it doesn't, well?

Thanks Mike for your quick response. The last modification was a couple of months ago; some time before I first noticed this problem. Having added a 2.5Gb hard disc to the original 170Mb some years ago, together with an Eidemax card to provide the necessary LBA (the BIOS is not upgradeable), I recently replaced the 170Mb with a 6.5Gb. With the Eidemax card and LBA already installed, the latest mod. was a straight swap with, apparently, no hitches. However, I have to agree that some change or other must be the cause. I should mention also that I have tried several times unsuccessfully during the last two years or so to load NT4.0 in a dual boot arrangement, to facilitate local area networking (WFW 3.11 unfortunately does not agree with the network hardware). However, NT4.0 does not seem to like LBA being provided by the BIOS extension instead of the orignal BIOS. After each attempt, I have re-formatted the C: drive and re-loaded DOS and Windows 3.1; so I should be surprised if this were the problem. The 'energy saving mode' words are mine. Without a screen saver set, the screen just goes black. I found many years ago that even legitimate screen savers can cause problems. I have not altered the Stacks= statement but could do as you say and set it to 0,0. What side effects, if any, could be expected from this? Once again many thanks for your advice. Kind regards, Jon G.

Check your email...

I don't think it's your stacks= statement, but I seem to remember back in the DOS/w3 days some folks thought that the stacks=x,y should have x=[number of sectors per track on the HD], often 17. So try 17,128 Shot in the dark. M2 If at first you don't succeed, you're about average.