Dual core for gaming?

[killer_uk]

Well let me know how it goes!

 

[Stelly]

Well let me know how it goes!

Will do as long as its not badly that will be ok with me

Stelly

 

[fish99]

oops indeed

 

[Stelly]

oops indeed

Yup people should learn to read the rules

Stelly

 

[NathanE]

Microsoft have admitted that the xp kenel could do with a lot of improving with regards to multi-processors.. they even said that VISTA would not include any enhancements over XP, but the next OS after that will !!

Another load of tripe. This thread seems to be full of it :/

FYI, Windows is more multi-threaded than any other mainstream OS. It's SMP support is second to none. With the NT 5.2 kernel they added NUMA support - further improving its support. Vista brings large enhancements for multi core processors too.

Other than in terms of licensing, the <=5.x kernel couldn't get a flying fudge whether you have a multi core CPU or not. The only time it modifies its scheduling behaviour (on a <=5.x kernel) is with a HT logical core. NT 6.0 will modify its behaviour a lot more with regards to multi core however. E.g. it will detect if you have a shared L2 cache and attempt to keep threads locked to that CPU but not neccesarily to a specific core as it currently does.

 

[Stelly]

Another load of tripe. This thread seems to be full of it :/

FYI, Windows is more multi-threaded than any other mainstream OS. It's SMP support is second to none. With the NT 5.2 kernel they added NUMA support - further improving its support. Vista brings large enhancements for multi core processors too.

Just ignore it mate, like I'm doing

Stelly

 

[Toytown]

Just ignore it mate, like I'm doing

The thing is, if you ignore it, then people generally consider the information to be true and they continue spreading the false information about. Its better to correct them, so that next time they post on the same subject (maybe even on a different board), there information will be more accurate (or at least a bit better)

 

[deadeyedic30]

Since my post yesterday the price of the X2 4600 has dropped by about £25-£30. God it's getting harder to resist.


Edit: I couldn't, ordered one, and an Arctic Freezer 64, and a Pioneer 111BK

 

[The Old Man]

again thats not true, since NT4 microsoft has had multi CPU support, this contuinue to windows 2000 and since Windows XP uses a modified Windows 2000 kernel it was designed with duel core in mind

Stelly

Yesterday I got flamed for posting about issues in Windows XP with dual core cpu's and by saying WinXP had isues with them because it wasn't originally designed for dual core cpu's. I was going from memory on an article I read in a magazine two months old and I don't yet have a dual core CPU myself. Other members of this forum have been flamed too it seems. However, here's some highlighted quotes from more reliable sources than your average forum jockey including Microsoft itself (no offence intended).

I've found the magazine (PC Format July 2006) and having read through it and done some brief research online, various parties a lot more qualified than me are saying the exact same thing. However, WinXP not being designed for dual core may not be the best description, possibly not ideally optimised may be better.

Having read though this and online, I would imaging this information has already been posted (and probably should be pinned) but here goes anyway.

It seems PCF have based the article on known hotfixes for dual core support in Windows XP, addressing problems that seem well documented online via a quick Google in terms of fluctuating performance (games slowing down, speeding up) and from what I've seen these issues are fixed with these hotfixes.

"So right now, you've got a dual-core processor running at the heart of your rig. Should mean a massive performance boost right? Except... somethings horribly wrong. Either games run too slowly, in some cases too fast, or most likely with little difference to a single core chip. Windows XP wasn't really designed for mulitple processors originally, you see, so your fresh-out-of-the-box new Athlon X2 or dual core Pentium D might not perform quite as expected. Fear not though, this can be fixed."

And that's what I recalled reading. However as I said its a few motnhs old and I don't have one of these CPU's.

From Microsoft themselves (link):

MORE INFORMATION
Windows XP SP2 is required on computers that have multiple CPUs that support ACPI processor performance states. This requirement includes computers that support the following items:
• Multiple physical sockets
• Multiple-core designs
• Multiple logical threads, such as Intel hyper-threading technology

Because Windows XP was not originally designed to support performance states on multiprocessor configurations, changes are required to correctly realize this support on multiprocessor systems. Windows XP Service Pack 2 includes the required changes to the kernel power manager. These changes make sure that Windows XP correctly functions on multiprocessor systems with processor performance states.

This hotfix also addresses the following issues on computers that have multiple processors that support processor performance states:
• A possible decrease in performance on single-threaded workloads when processor performance states are using demand-based switching.
• The synchronization of the processor Time Stamp Counter (TSC) registers across processors when you use the ACPI Power Management timer on multiprocessor systems.
• ACPI C-state promotion and demotion issues in the kernel power manager.

As I said, I imagine this is posted elsewhere but just in case here's PCF's advice:

1. Low Power States, where the cpu is throttled according to the demands placed upon it, means processor fans aren't as noisy as they used to be. trouble is there is a bug in XP that means some dual core CPU' don't always throttle back up, resulting in errant performance.

2. Fortunately there is an official fix from Microsoft:

Computers that are running Windows XP Service Pack 2 and that are equipped with multiple processors that support processor power management features may experience decreased performance

Unfortunately it won't give it to you unless you ask. However it is also hosted here at AMDZone. (Its only for Windows XP w/SP2 per the documentation.) (It works for AMD and Intel chips, mind.)

3. You have to do a spot of registry editing after installing (back up your registry first/create a restore point)...

1. Click Start, click Run, type regedit, and then click OK.
2. Right-click HKEY_LOCAL_MACHINE\SYSTEM\Curr entControlSet\Control\Session Manager, point to New, and then click Key.
3. Type Throttle for the new key name.
4. Right-click Throttle, point to New, and then click DWORD Value.
5. Type PerfEnablePackageIdle for the value name.
6. Right-click PerfEnablePackageIdle, and then click Modify.
7. In the Value data box, type 0. Make sure that Hexadecimal is selected in the Edit DWORD Value dialog box, and then click OK.
Note You can type 1 in the Value data box to enable the new performance state policy behavior.
8. Quit Registry Editor.

Also note that in the DWORD value box (step 7), you enter a "0" to disable the power state created by the hotfix and enter a "1" to enable it. For the purposes of fixing the games, enter a "1".


Got an AMD X2 that's playing funny buggers? Depending about which forums you browse, you may have been subject to bitching about AMD's dualie's performance. The troubles reportedly stem from both cores not always being in sync, and again AMD offers a fix for this.

Grab it from http://tinyurl.com/84r89.
If you runing an Intel chip, you can do it manually:

Go to Control Panel>System>Advanced. Click on Settings under Startup and Recovery. Click Edit and then add /usepmtimer to the end of the last line and save it.

Your dualie is now performing as efficiently as it should so give it a work out. The most noteworthy dual-core friendly games of the moment are Quake IV and Call of Duty 2, both of which offer performance boosts if you patch them and then enable multi-threading.


For more related info on this that I found online:

How to install the AMD X2 drivers, hotfix, the correct way.

AMD Athlon™ 64 X2 Dual Core Processor Driver for Windows XP and Windows Server 2003 Version (x86 and x64 exe) 1.3.2 - Allows the system to automatically adjust the CPU speed, voltage and power combination that match the instantaneous user performance need. Download this Setup Installation program (EXE) to automatically update all the files necessary for installation. This package is recommended for users whom desire a graphical user interface for installation. This .EXE driver is a user friendly localized software installation of the driver designed for end-users. This driver supports AMD Athlon™ 64 X2 Dual Core processors on Windows XP SP2, Windows 2003 SP1 x84 and x64 Editions.

Dual Core Gaming Fix Guide

Hopefully this information may help dual core owners get the best out of their CPU's and again I apologise if its been posted already.

 

[NathanE]

The Old Man: When Microsoft says "performance states" it is referring to the CPU running in an unrestricted or mobile (or some level between the two) power mode (i.e. SpeedStep/CnQ). All of the multi core problems (like games running slow-mo or super-fast) stem from ACPI trying to keep power consumption to a minimum. Windows XP originally did not have complete ACPI power management support (read: bugged) for multi core processors but that hotfix adds/fixes it and actually adds the ACPI driver as is found in NT 5.2.

Just to clarify, this hotfix does not alter "performance" (i.e. benchmarking) of your PC. It merely adds proper support for SpeedStep/CnQ on SMP systems.

 

[The Old Man]

Thanks!