My friend has system with Pentium Dual Core E2180 running at 3GHz, 3GB of RAM, 250GB HDD, 8800GS 384MB with additional power port for PCI (on MB), dial-up modem, skystar 2, bluetooth and he has some cheap 400W PSU...
So in case I don't get any answer, I will go for that Fortron 400W and may God help me that I don't make a mistake that will cost me 35EUR...

The E2180 is a low-power chip made for HTPCs, so I don't think you can compare it to a 45nm mainstream desktop CPU. But the E8400 should allow for some headroom...
Anyways, keep us updated.

Well, I don't know anymore what to do...
I'll go now to buy RAM, and I'll see with the guy at the store which PSU to buy, I may even go for this Chieftec, I think...
Anyway, I'll inform you what I've done and if I manage build it this weekend post some benchmark results...
Thnaks a lot

IMO, if going for a PSU other than the Fortron, go with the one with the highest total wattage, since it's atleast guaranteed not to overload.

Well, I've bought a FORTRON SAGA plus450P (it says on the box up to 500W) so I think this one should be fine...
I also bought 2 x 1GB of Kingston RAM (I've read that it's better to have two sticks, since PC can access the memory at the same time), and ordered E8400 for tomorrow, so with God's help, I'll build it tomorrow...

I have a problem!
I've built the rig, powered on the system, everything works fine, even MB recognizes CPU without BIOS update, but when I tried to install Vista, bang, a problem...
It does not recognize my HDD and I cannot install OS on it... BIOS detects it but not the OS... I've taken it to my friend, and his PC recognizes it in BIOS, and when we loaded Windows XP, it found new drive, and it is there in the Device Manager, but there is no drive in My Computer... In Safely remove devices, there is my friend's disk and drives E:, C: written, but next to mine, there is nothing, just the model number.
When I try to boot from it, computer simply restarts...
I gave it to another friend before I built my system and his PC recognized it, he made two partitions 146GB and the rest on the second to which he copied some things for me that I wouldn't have to download on dial-up.
XP installation recognizes the disk, but only as 135GB and it formats it and copies the installation files and when it restarts, nothing, all the same, it starts installation again...
Is there anything I could try to do, or should I return it to the shop and ask for a new one?

Great job, glad it worked out for you.
As for the HDD, it's better to just return it and get a new one. It'd be easier than wasting your time trying to salvage a defective one.

Thank God, I've made it... well, I'm writing this from my new PC...
I managed to make it work, installed Vista 64bit, but I am not quite impressed with performance... I got 5.6 on Vista experience (CPU 5.7, RAM 5.6, rest 5.9), and I tried to play Crysis, without patches and with the drivers that came on CD with card (since all those things were on the other partition, and all is gone) and I barely got average 25fps on 1440x900 DX10 High settings...
I also experience occasional slowdowns when working in Windows, but I guess it's just until it all gets to work together...
Anyway, thanks for your help, I hope I'll be able to help other people on this forum who need help...

Vista SP1, newer drivers and the latest patch for Crysis should fix those issues. Did you try other games though? UT3 should be a breeze to run at that resolution IMO.
Anyways, glad to know it worked out well and good luck to you. Enjoy your new PC!

Well, I tried NFS Pro Street, and it goes some 50fps with everything on the maximum, and Call of Duty 4 is locked at 60fps and falls sometimes to 55, with everything maxed out... and some 5-6 explorer windows and kaspersky update in the background running... I guess it's Crysis being ahead of time, not my computer that's problem...
Asus PC Probe shows CPU temperature 35 at startup, and after playing it is 60 (is it high?) and MB temperature is constant at 41-42, while CPU fan spins 2500-2700...

Nah, 60C under load is okay. Everything looks good to me.

I got two times PC Probe alarm after an hour or so of playing, MB temperature went to 46, so is it dangerous temperature or it gives alarm as a warning...
Maybe to rearange cables in the case?

There is something definitely wrong with the board...
I played Crysis now and the PC restarted and when I turned it on again and PC Probe showed me motherboard temperature 49C...
Nothing is overclocked except the graphics card...

I'd check the CPU temps too. Also, try re-seating the CPU HSF and re-applying the thermal compound. You might try adding more fans to the case and keeping it in an air-conditioned room.

Well, the CPU goes to 60-65 under load, but as soon as I minimize the game, it decreases to 45, and then after some time goes back to 35...
I've read that people are running this board at 55C, and my friend has Abit MB which has alarm on 55, so should I also raise the sensor sensibility?
I will also get 1-2 fans as soon as possible, but I would like to be able to play 1-2 hours without interruptions...