my sr1536nx presario , is there a motherboard processor replacement that will fit in the case. i bought the conan game and now i'm in deep kimshee. my processor,power supply and vid card have to be upgraded. so i wonder if i can upgrade everything and still use the same case. i want to give this comp to my son but i really would like to wait until i can boost it some.

While having a google, I found this quote which may assist your graphics card choice:

Default Re: K8S-LA (Salmon) Video card compatibility, Radeon X1950 pro, GeForce7600GTGT
I unfortunately have had some experience with this board as I had
purchased 2 units containing them a few years back. The Geforce 7600 by
PNY did not work properly on this board even with power supply upgrade
and latest bios. The problem with the PNY Geforce 7600 appears to be
coming possibly from a bug in bios firmware with periodic stuck on bios
screen problem. Since this is an ASUS OEM board with support only from
HP/Compaq this is a dead issue. We have had success with ATI 9250 256MB
with no problems without upgrading Bestec power supply. I am currently
running a ATI 7600 on the unit with the upgraded power supply with no
problems. Best of Luck.

FROM HERE (final post)

THIS PAGE shows the specifications of you computer. It says you have an AMD Athlon 64 3200+ running at a speed of 2.2GHz (you can check this by right-clicking on 'myComputer' and going to properties, look in the bottom RH corner). Now, you could replace that with a higher speed processor (like a 3400+ @ 2.4GHz), but I don't think it's really worth it. Any performance gains will be fairly minimal.

A graphics card is your ticket to freedom, just be aware that you've got an AGP slot, not a PCI-e. I have the same slot, and use a Gforce 7600GT which works really well. I was going to recommend it until I read that post I quoted above...

do you happen to know where i can get an upgraded power supply that will work in this case. the one i have is only 250 watt and that wont work with the vid card, or so it says.

take the psu out and take it to local computer shop and get a matching psu ,should be just a standard atx psu

I've got a feeling these putas use a m-Atx PSU, so it could be hard to find a powerful flavour. So yeah, taking it to your local computer shop for a replacement is a good idea.