slow logon and install programmes

amount of RAM available?
Did your windows 7 as well lag?

no I didn't had lag at w7, I have 4 gig of RAM

I forgot to say there's 3,5 gig of ram available

I don't bother with oc, just read about it; that does seem like a large oc, though, from the standard 2.7GHz? Try backing that off [that's the first rule on a badly performing oc job, isn't it?]. Does it game ok? Check your memory with Memtest86+ [the bluescreens suggest a possible problem].
But sometimes installations just seem to go bad, little bits of sysfile corruption that slow things down. If just a few weeks into it, I'd consider a reinstallation. I know it's a pest, a time waster, but sometimes it works. A last resort, though.

How many memory did you left. I am 14 but from singapore. Different country but same age;)

Try doing a malware scan using malware bytes. Also check whether your anti virus software has detected anything. Have you downloaded any apps recently, if yes try removing them and see whether the login time is faster. Where do you install apps from? If you download applications from the internet and it is slow it may be your browser problem or your internet connenction. Check your internet speed and try changing browser to see whether downloading other softwares take a long time. Post back your findings. Good luck!

check also background processes running in the task manager, some can be closed to speed up the system, like wise for some services running, and also check virtual memory settings as well
btw 4GB is more than required to run xp, so i dnt think its a memory problem, but still run the test as suggested by gerbil if needed

At logon there won't be a whole lot of background pgms running, certainly no third party apps, and the internet connection quality will hardly be a bugbear then. Most malware won't have started at that time [cannot be ruled out, though]. Sure, 4 GB of mem is more than XP can recognise, but one bad bit is one too many. Bluescreens with W7, slow login with XP...

defragment! get it to 0%
also check disk for errors
these are easily found in start menu programs accessories system tools

your computer should not be having problems running windows7...it seems like a hardware problem possibly due to the overclocking...i would need help myself

-edit-also check for video card driver updates

At logon there won't be a whole lot of background pgms running, certainly no third party apps, and the internet connection quality will hardly be a bugbear then. Most malware won't have started at that time [cannot be ruled out, though]. Sure, 4 GB of mem is more than XP can recognise, but one bad bit is one too many. Bluescreens with W7, slow login with XP...

Not sure concerning the processes, the lad may have an antivirus kit loading, and I know some antivirus which start scanning as soon as you logon, in the background. But could also be a hardware problem somewhere like you mentioned, a heavily fragmented hard-disk
Am on Windows 7 for a long time on a Pentium D and no BSOD or any crash for nearly 8 months now, so it could be a hardware incompatibility issue, or in case of overclock, reset the bios to default to see how the system behaves

What i said before is that 3rd party apps may bog down the whole system thus making it slow when starting up, not necessary the application must be running.

Yeah. OP is not giving much detail - we don't know if it is slow coming to logon screen, or after. Big difference regards third party apps.. most won't load until userinit.exe runs.
As far as boot scans by AVs, Avast can be set to do one, but it is obvious, with an info screen; it runs before winlogon.exe.

thanx for the reactions.

I will give it a try to reset the bios to original settings.

I did reset the bios back to original problem stil persists. ( logon )

but installations go faster now.

the computer start fast but when the pc comes to the logon screen it stays for 2 minutes or more at : windows wordt gestart ( windows starting).

I have tryed everything clean reggstery with ccleaner and clean computer with ccleaner.

I did run a virus and spy/adware check with microsoft security essentials and found nothing.

in the Run... line type msconfig or msconfig.exe or msconfig.msc
click the 'startup' tab to see what is running at startup.
click the 'services' tab to see services you might want to disable.

try to use drwatson.exe(or whatever it's called) to scan for hardware problems

search 'pcdoctor' online that is another hardware scanner

even a newly installed OS might still need to be defragged

defragging right now.

Jeannot, "the computer start fast but when the pc comes to the logon screen it stays for 2 minutes or more at : windows wordt gestart ( windows starting)." implies that your sys is having trouble either with services or drivers and hardware. It is at that point that ntoskrnl is loading services [drivers] from the list passed to it by ntldr [the default controlset], and seeing whether the hardware functions. So when you next start your sys check in device manager for any devices with a yellow "?" next to them. That will indicate either a bad driver of hardware item.
To find a sticky service is tougher. If you have tried your Restore Points and they do not help, then try the following:
Just to be safe, first start your sys in Safe Mode. Works? Right, run msconfig [from Safe Mode will do], and under Sevices tab check the Hide Microsoft Services box, then uncheck all that remain [except any for your keyboard], including your AV and firewall. Restart. Recheck the boxes if no change.
Under General tab select Diagnostic Services and restart [you will lose ALL restore points if you do this...]. No change? Set it back to Normal start.
Say how you get on...

thank you for the reaction, I've defraged the pc but no change.

I've do what you said Gerbil, but it doesn't work.

Hopefully, I will solve this with all of you.

Hello, jeannot, well, we can rule out malware [you scanned] and non-M$ services, and probably drivers. Hmm... did you check the Event viewer [via Admin tools]?
And did you run Memtest86+ [from http://www.memtest.org/ ? Halfway down that page you have a good choice of builds for floppy, cd or USB.
The only other thing I can suggest to nail this down is to get and run Process Monitor from http://technet.microsoft.com/en-au/sysinternals/bb896645 -put it somewhere for fast access, perhaps into a new folder on your desktop.
You need to boot log with it, so start it via procmon.exe and halt the logging immediately via the little magnifier glass; go Options > Enable Boot Logging.
Restart your sys; when you are able start Process Monitor, answer No to saving the log and immediately stop the logging.
Add the Duration column. You are looking for anything with a duration longer than oh... to start with... maybe 0.02 seconds. Easiest is to set a filter for that; use Duration Less than 0.02 then Exclude. Add and Apply that.
That filter should leave you with a few disk accesses, reads or writes. Too much info? Your sys is slow...Increase the filter time to 0.1 sec... there should be nothing. But something is dragging its feet, and this might bring it out. To modify a filter find it in the list, dclick it to put it in the edit line, vary it, Add and Apply.
Post about what you find. But please, do NOT post the log.... it will be MASSIVE.

In the log are lots of files with acces denied and buffer overflow error.

sorry for the late post have lots of homework.

Hi, Jeannot. Buffer overflow results are normal; the query will be remade but with allowance for a longer data reply; there may be 100 or 200 of them. Another common result is Name not found - the software is written for many eventualities.
But Access denied? - I have not seen that in a Boot log. What processes were involved? [use filter: result exlcudes denied then exclude]

Gee... I led you astray there. It's been a while since I did a boot log.... so I did one just to check. Here is the proper way... :( :
To do one, run procmon.exe; stop the logging via the magnifier button. In Options, check Enable Boot Logging, and restart your system.
Upon the restart, boot logging will halt the moment you run procmon.exe; then choose to Save the log somewhere [it will be 200MB more or less if you stop it quickly; the logging continues until you run procmon.exe].
Once Saved [and only when saved], the log will be presented in Process Monitor's window.
As far as setting a Duration filter goes, you may need to play a little bit with its time values. Using Duration is only a start - some processes continue without interrupting the startup. For example, winlogon.exe runs continuously once it starts, so will explorer.
Really, what you are looking for is large jumps in Relative Time, but I don't know how to filter for that... scrolling and eye-balling the column will always work.
You might also try disabling your AV and restarting.
Access denied... there will be a few relating mainly to Winmm access requests.

I changed comodo firewall settings and the pc boots fast, It's solved.

Thank you everyone.

Cool,i did not know comodo firewall could even cause the problem.:D
But also do remember not to turn off the firewall, the firewall in anti virus software is essential to protect your laptop against virus. See you:)

What setting was that, Jeannot? I use Comodo.. I know it starts with other boot-time drivers, but it hardly slows things down.