reinstalling windows

[jayder]

hello all,

i'm tryin to reinstall windows on a computer that had alot of virus on it. i went to the bios and changed to boot from cdrom first and put the xp pro cd in and rebooted everything came up but whe it got to(hit any key to start it stop right theree and didn't go no father .what should i do?

thanx
jay adams

[rivimey]

The "hit any key" - was that something like "Press any key to boot from CD"?

Did the screen change to a blue background at any point?
Did the CDROM spin up (could you hear it)?

If the CD didn't spin and the screen didn't go blue background, you haven't started booting the setup process. In this case, either:

- you were mistaken in thinking you'd set to boot from cd. double check.
- one of your viruses has messed up the BIOS.

I am reluctant to suggest anything drastic without more confirmation, but if you feel confident in configuring a BIOS, I would suggest finding out how to reset the BIOS (usually removing the battery) and then trying that.

Ruth

[MartyMcFly]

I'm thinking similar things Ruth.

Several posts have Bios problems, perhaps someone with Bios expertise could assist. Do you remove the battery for say 10min or do you need to "Flash" it?

[rivimey]

The memory the BIOS uses is not normally FLASH memory but battery-backed SRAM.

Flash memory = memory that is constructed so that it can be read as normal and written in a special way so that data is not lost if the power is removed. The downsides are that it is more expensive to use, is harder to build in the same chips as other devices, and when writing you must erase a whole block and then rewrite what you want to the whole block. Block sizes vary from 256 bytes in small chips to 64KB in larger ones.

SRAM = memory that is fast, easy to use, and easy to integrate onto chips but loses its contents if the power is removed.

Battery-backed SRAM is a normal SRAM which has a battery connected along with another power source such that if the other source fails the battery will take over.

Normally, the battery is a small "button" cell, CR2032 or CR2024, but the type does vary. You can remove them quite easily. They should last in normal conditions for between 4 and 6 years before having to be replaced.

Removing the button cell will be effective within a few minutes; you might like to leave it 5 or 6 mins to be sure, although it might only need, say, 2. The reason the effect is not instant is twofold: (a) the battery consumes a very tiny current - usually a few microamps (millionths of an amp) and (b) there are capacitors on the power supply to "smooth" the current spikes caused when transistors switch on or off. These take some time to discharge into the RAM and for the RAM itself to loose its current.

So in summary:

- You don't (normally) "Flash" a BIOS RAM

- Between 5 and 10 mins is a good time to let it erase, although it might not need that long.

- There are some motherboards that store some information elsewhere, e.g. passwords in true FLASH ram, or in a separate device, which won't be erased by removing the BIOS battery.

In general, it's best to check the manual for the BIOS before playing with these areas. There are too many "gotchas" for it to be simple.

Ruth

[Catweazle]

Hi jayder,

Is this a legitimate retail or OEM Windows XP Pro CD? If it's a copy it may not be bootable.

[jayder]

i did take the battery out and everything .i just can't get the cd to boot it just stay on the screen say hit any key to start windows and stay there i wait for a min and it just sit there.

[jayder]

and i can hear the cd moving in the cdrom but it's not doing anything

jay

[Catweazle]

Three possible causes:

* The CD-ROM drive is faulty
* The Windows CD is dirty or scratched, rendering it non-functional
* The Windows CD is a poorly made copy, which is not bootable.

[jayder]

i just used that cd and the cdrom is good

[Catweazle]

Has the computer got more than one RAM module installed? If so are they different brands?

If this is the case, then remove all but one RAM module, and ensure that the one you retain is in RAM slot 1. Then try to install. Windows XP is particularly 'fussy' with RAM mismatches.

[gerbil]

jayder, to flash your BIOS, power off, remove battery,...there is a jumper that u reverse momentarily on the motherboard nearby. refer to motherboard book to locate it.....or if ur not up for this, yep, leaving the battery out while u brew a coffee will do it. replace battery after jumper is returned to original spot, restart and hit delete, enter bios and load defaults. put cdrom before ide drive in boot order. save changes. and if that does not work, get a new cd.

[Catweazle]

gerbil, the jumper shorting method does NOT require removing the battery ;)

It does, however, necessitate having the correct instructions available in the motherboard manual, and these are seldom supplied with 'brand name' PCs.

[gerbil]

thanks about that for the jumper/battery, cat....i just was not sure how much the reverse jumper posn would load the battery..but since sram consumes only a handful of microamps, it is logical that there would be a high impedance supply circuit in there...And isn't it a shame that sometimes you do not hear how folks solved their problem?

[Catweazle]

gerbil, it's a shame that people try to micro-analyse procedures such as this, instead of simply finding the instructions and following them!

:D