Hard Drives not detected

[#1]

Battery is cheap enough to replace so I'd suggest doing this as a matter of course anyway. As a general rule most cmos batteries will last at least 4 years but good practice would be to replace them every 2.
The capacitors are tall round things with a silver top and 2 legs at the bottom. Sometimes the legs aren't visible as they're soldered as close to the board as possible. Typically if a capacitor has failed, the silver bit at the top will be bulging (IE looks like pressure built up inside and it wants to explode) or it will be leaking a yucky looking substance. If you don't have the tools to desolder them and replace them yourself there is nearly always someone at the local TV repair shop who will for a fiver
Those aren't guaranteed to cure it but are certainly 2 possible causes which I've noted in the past on other systems.

[#2]

I need to try replacing the cables first as the problem has started up again and I reckon the dodgy connection on one of them could be the cause of this.
Is this possible?
One cable is red Serial ATA and the other is silver - are they different, should I be replacing them with the exact same ones or can I get a generic cable?
Thanks

[#3]

Colours are usually irrelevant but I would always recommend getting SATA2 cables with a locking mechanism.
You can also get right angle ones if needed

[#4]

Thanks Old Jim,  that's sound advice.
Where's the best place to buy them, Maplins?
Do you have a link to a picture so I can see what they look like (I know, I'm a lazy B.....)

[#5]

So am I - so here is a picture of one I had beside me

[#6]

Thanks Oldjim.... nice picture.

[#7]

Ok, I've tried everything I can with this hard drive and I even bought a UNITEK SATA HDD docking station which works pretty well for the secondary drive but doesn't read the primary so I'm assuming this means the primary drive is unaccessable.
I would still like to try the drive out on another pc which I have running W98, will this work (obviously only if the drive is functioning),
I also want to try and revive the original PC again but not sure how do check the mother board. could I connect the one from theW98 PC?