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'WinXP Home 32 Bit' and 2 x 2 GB DDR2 RAM ?
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Author | Message |
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Sutaru Tsureku Send message Joined: 6 Apr 07 Posts: 7105 Credit: 147,663,825 RAC: 5 |
I had 2 x 1 GB 800 MHz/5-5-5-18 DDR2 RAM. And WinXP Home 32 Bit saw 2 GB RAM. Now I insert 2 x 2 GB 1066 MHz/5-5-5-18 DDR2 RAM in the mobo. (MSI K9A2 Platinum) The AMD Phenom II X4 940 BE support 1066 MHz DDR2 RAM. But now.. "Systemsteuerung/Leistung und Wartung/System" I read 2.25 GB . 'System Control/Performance and Maintenance/System' CPU-Z see 4 GB RAM. What's going wrong? Thanks! |
Fred W Send message Joined: 13 Jun 99 Posts: 2524 Credit: 11,954,210 RAC: 0 |
You've run out of address space. 32 bits can't address 4G of RAM. For that you need to go to 64 bit OS. F. |
Sutaru Tsureku Send message Joined: 6 Apr 07 Posts: 7105 Credit: 147,663,825 RAC: 5 |
I don't need 4 GB system RAM.. ;-) For me was important to have 1066 MHz system RAM. My OS (also the RAM) will be running well, of will do now errors or some other 'crazy' things? |
Nemesis Send message Joined: 14 Mar 07 Posts: 129 Credit: 31,295,655 RAC: 0 |
Fred is correct, it's an addressing limitation when using a 32 bit OS. That being said, you indicate only 2.25 visable by the OS, it should be more in the range of 3.25 to 3.5 depending on how much is allocated to hardware extensions by the BIOS. That 2.5 seems a bit too low... |
Sutaru Tsureku Send message Joined: 6 Apr 07 Posts: 7105 Credit: 147,663,825 RAC: 5 |
It's only 2.25 GB system RAM now. I have 4 x GTX260-216 installed. Because of this ~ 1 GB less and only 2.25 GB available? |
Iona Send message Joined: 12 Jul 07 Posts: 790 Credit: 22,438,118 RAC: 0 |
I have to agree with Nemesis, 2.25 GB does seem rather low. I tried out something similar on one of my PCs (MSI P35 Express Platinum m/b), already knowing the limitations of the 32 Bit OS and had about 3.2 GB available. The RAM was Patriot DDR2 800, running 4-4-4-12 - thats normal settings and much cheaper than the equivalent spec stuff from my more usual OCZ. Don't take life too seriously, as you'll never come out of it alive! |
Jörg Send message Joined: 10 Dec 02 Posts: 51 Credit: 1,547,286 RAC: 0 |
Hello, in the Bios of my Mainboard is a feature called "memory remap" (or so) that I had to enable to get 3,5 GB of my 8 GB working under Windows XP 32bit. Without enableing this feature I had around 2 GB too. Am Ende ist nur Verwirrung |
Nemesis Send message Joined: 14 Mar 07 Posts: 129 Credit: 31,295,655 RAC: 0 |
It's possible that it's caused by your hardware. The are memory mapping utilities that will show how your physical memory is mapped out, which areas are BIOS reserved, which areas are used by the kernel and all the other processess etc.. It's actually quite interesting, unfortunately I can't find the tool I used to have for this and I'll be damned if I can remember the name... You can always do some searching on the web if you are so inclined... |
Pappa Send message Joined: 9 Jan 00 Posts: 2562 Credit: 12,301,681 RAC: 0 |
Shut the system down, wait ten seconds. Styart the System pressing the Del Key, F2, F10 or Crtl S or what it takes to get into yur system Bios on Startup. When You get in, look at the "Basic System Information" to see how much RAM it reports. It should say the whole 4 gig. IF it does not you could have a couple of issues... The is not seated properly. The Bios is not recognizing the RAM (your might require a Bios Upgrade). The worst is you have Dead RAM. If it recognizes the correct amount, SAVE and Exit. this will update the DMI Information that is reported to the OS. Then look to see what the OS Reports. Please consider a Donation to the Seti Project. |
Ianab Send message Joined: 11 Jun 08 Posts: 732 Credit: 20,635,586 RAC: 5 |
The 4gb RAM limit imposed by the operating system includes the space used by the Graphics cards. If you have a basic video card you should end up with around 3.9gb of ram available to WIndows. 1 x High end card will reduce that to a bit over 3gb max Multiple high end cards, even less free memory space. The system should function fine, it's just that windows cant access all the RAM, so it ignores what it cant see. If it's a dedicated cruncher it will run fine with 2gb of ram available. If you use it for other stuff that needs more RAM, best to upgrade to a 64bit version of windows. Ian |
Juha Send message Joined: 7 Mar 04 Posts: 388 Credit: 1,857,738 RAC: 0 |
Funny you should ask it now. Just the other day I read about this: The Old New Thing : Why can't I see all of the 4GB of RAM in my machine? Your computer info says [4] NVIDIA GeForce GTX 260 (895MB) Is that misleading and are those really two times two GPUs sharing 895MB of memory? If each GPU had 895MB of memory that would total to 3580MB - leaving around 500MB of 4GB usable... -Juha |
Ianab Send message Joined: 11 Jun 08 Posts: 732 Credit: 20,635,586 RAC: 5 |
His system board has 4 x PCI-e slots, so I'm guessing he has 4 cards in there. http://www.msi.com/index.php?func=proddesc&maincat_no=1&prod_no=1332 I'm guessing that the system doesn't map all of the graphics ram to the CPU? Maybe 500mb per card? I dont have one of those cards yet, so I'm only assuming. Ian |
Juha Send message Joined: 7 Mar 04 Posts: 388 Credit: 1,857,738 RAC: 0 |
His system board has 4 x PCI-e slots, so I'm guessing he has 4 cards in there. Perhaps. Then again, 2*895MB = 1790MB, 4GB minus that gives about 2.25GB which is what Sutaru is seeing. ---- It would be a fun experiment to take a machine with 32 bit OS, stick four or maybe even five video cards, each with 1GB video memory, into that machine and see if and how the system breaks. That kind of configuration should use all address space - leaving nothing for OS. -Juha |
Cruncher-American Send message Joined: 25 Mar 02 Posts: 1513 Credit: 370,893,186 RAC: 340 |
Hey - as I understand it, the whole point of having memory on the video card is so that it is not mapped from the CPU memory, but is separate (and unknown to the MB). But the other points about 32bit OSs are correct - perhaps the 4 video BIOSs take up more room and bring the system memory visible to 2.25GB from 3+GB? Just how big ARE the BIOS for those cards? FYI: I am running another machine with one video card (7300GT) on 32bit Vista, and it shows memory of 3,070MB out of the physical 4GB attached. |
dnolan Send message Joined: 30 Aug 01 Posts: 1228 Credit: 47,779,411 RAC: 32 |
This Ask Dan article gives a pretty good explanation of the relationship between memory and the OS and other devices, if you're curious. -Dave |
Juha Send message Joined: 7 Mar 04 Posts: 388 Credit: 1,857,738 RAC: 0 |
Hey - as I understand it, the whole point of having memory on the video card is so that it is not mapped from the CPU memory, but is separate (and unknown to the MB). I thought the idea was to store textures and whatever you need to draw graphics into video memory so you can access it faster than if it was fetched from RAM over AGP/PCIe/some other bus. But the other points about 32bit OSs are correct - perhaps the 4 video BIOSs take up more room and bring the system memory visible to 2.25GB from 3+GB? Several hundred megabytes for BIOS? Oh come on, that would be like embedding Windows into BIOS! -Juha |
Westsail and *Pyxey* Send message Joined: 26 Jul 99 Posts: 338 Credit: 20,544,999 RAC: 0 |
Been wondereing about all this myself.. Running a 4gb 2channel kit with xp32. Host has 2 GPUs, video memory is about ~1.5gb host 5007936 Here is my other host: 2x1gb kit + 1GB GPU host 4984873 (sorry keyboard no worky so cannot screencap that one right not) Same graphic as above: reports 2.00GB in system properties and task manger shows 2095596k Total "The most exciting phrase to hear in science, the one that heralds new discoveries, is not Eureka! (I found it!) but rather, 'hmm... that's funny...'" -- Isaac Asimov |
Sutaru Tsureku Send message Joined: 6 Apr 07 Posts: 7105 Credit: 147,663,825 RAC: 5 |
Thanks to all! :-) Now small post of me.. I was/am little busy. If I forgot to answer a question, will do later. For more infos. My GPU cruncher is running since February with 2 x manufacturer OCed GTX260-216. Since May with 2 more, so 4 x the same manufacturer OCed GTX260-216. With 800/5-5-5-18 DDR2 system RAM, 2 x 1 GB. I read, that with an AMD Phenom II X4 (940 BE) you can't go higher as 1.80 V with the system RAM, if yes you damage the CPU because of the insert RAM controller or something. This CPU support 800 and 1066 MHz system RAM. Then I read they are 1066 MHz DDR 2 RAM out with @ 1.80 V. I bought OCZ PC2-8500 Platinum Low Voltage Dual Channel (only 2 x 2 GB) http://www.ocztechnology.com/products/memory/ocz_pc2_8500_platinum_low_voltage_dual_channel I insert this new system RAM, started the PC pressed 'Del' for to go into BIOS, but I saw then a screen with many colored dots. *surprised* Then I pressed 'Reset' at the PC case and Windows was loaded. I made reboot for to look to the BIOS and changed the RAM voltage from AUTO to 1.8 V for to be sure/safe. I can see only the CPU and system RAM speed in my BIOS. The BIOS isn't very userfriendly/informatively. No info about installed RAM size. For to now I didn't found the overview for to change for example the latency of the system RAM.. oh well. Maybe not possible. But not important for me.. ;-) Then the PC was running well. The only strange, like I posted here that WinXP see only 2.25 GB system RAM. CPU-Z see all 4 GB. O.K., now we know.. ;-) ..WinXP 32 Bit is limited with system RAM.. O.K. ..a pity.. but O.K., my whole GPU cruncher take 'only' ~ 700 MB if CUDA crunching. So it's well. I made a test, switched OFF the PC, took one system RAM out and started the PC with only one system RAM. And Win saw the full 2 GB system RAM. Insert again the 2nd system RAM and Win saw again only 2.25 GB. So I have only 2.25 GB system RAM for usage. In the time I had 2 x 1 GB system RAM, I had the whole 2 GB system RAM for usage.. So if I go higher as 2 GB system RAM, the 32 bit OS reduce it.. yes? But.. now.. after maybe 24 hours crunching I hear the GPU fans are quiet.. I looked and Win was frozen. No chance to do anything.. pressed the reboot button on the PC case and got the message 'no bootable device' or something. O.K., switched OFF the PC waited 1 minute and switched again on and after some sec. I see Windows. Everything well.. hmm, maybe not.. :-( I guess because of the new RAM.. maybe the 1.80 V is too low?? The new RAM must be the reason, I guess. The manufacturer say I could set 1.85 V for OC.. without losing the warranty.. but.. hey, with this I will damage my new AMD CPU ? What you think? The RAM is the reason of the frozen Windows? It's true because of the AMD CPU and don't go higher as 1.80 V system RAM ? BTW. It's a pure GPU cruncher.. After changing the system RAM from 800/5-5-5-18 to 1066/5-5-5-18 the calculation time is now ~ 1.75 % faster. You would say now.. and? But if I calculate.. 0.44x AR WU (89.x Cr.) in ~ 570 sec. .. 6.32 WUs/h -> 151.68 WUs/day -> 13,499.52 RAC/GPU/day -> 53,998.08 RAC/4 GPUs/day --> + 1.75 % -->> 54,943.05 --->>> + 944.97 RAC/day .. -->> :-D BUT now.. not possible because of my AMD CPU and the not running system RAM @ 1.80 V.. or what? :-( |
Cruncher-American Send message Joined: 25 Mar 02 Posts: 1513 Credit: 370,893,186 RAC: 340 |
Hey - as I understand it, the whole point of having memory on the video card is so that it is not mapped from the CPU memory, but is separate (and unknown to the MB). You're right about the BIOS - my bad. |
b101uk Send message Joined: 11 Jun 01 Posts: 37 Credit: 282,931 RAC: 0 |
As I see it and according to an article I read on the MS site (/3gb /pae switches - busting the myths), Windows 32bit are software limited to 4gb of address space as a function of 32bits If a 32bit MS OS is running in PAE mode then it is using 36bits so is able to address space >4gb but as windows OS 32bit/36bit is software limited to 4gb you don’t see it though it is in use as virtual memory. The latter means applications that are aware can see space above >4gb and the 36bit (PAE) MS OS see’s this space >4gb as virtual memory much like the “page file†is. As an e.g. I run XP 32bit SP3 in PAE mode (36bit) I have a GTX275 and 6gb of ram and page file is totally disabled, windows reports 3.25gb of ram, aware applications see 6gb of ram, files that are residing in virtual memory that would normally be in the “page file†(HDD pagefile.sys) now resides in the ram space >3.25gb <6gb as the virtual memory part of any program, i.e. if an application has a 2gb footprint in the ram and a 1gb footprint in page file/virtual memory then the 2gb part subtracts from the ram space <3.25gb, the 1gb part that would traditionally reside in the “page file†(HDD file pagefile.sys) part of the virtual memory now resides in the RAM space >3.25gb which is virtual memory. Bionic reports Memory: 3.25 GB physical, 3.09 GB virtual with page file disabled, if I define 5gb of page file then Bionic reports Memory: 3.25 GB physical, 8.09 GB virtual of which 5gb will be HDD (pagefile.sys) virtual memory address space >3.09gb <8.09gb (>6gb ram total) and the rest physical ram portion of the virtual memory address space >0gb <3.09gb (>3.25 <6gb ram total) I put the discrepancy between 3.09gb + 3.25gb = 6.34gb rather than the true xxxgb + xxgb = a true 6gb ram due to shoddy conversion factors for conversion values and truncation in decimal point precision given the potential for the amount of times something could be multiplied etc to get from the smallest whole units like 1bit to the largest part unit like a gigabyte and Decimal vs. Binary values I.e 1000 vs. 1024 ware it is displayed to the end user but this value is not used by the OS/PC Either way 3.25gb reported ram by windows + 8.09gb virtual memory of which 5gb is HDD space and 3.09gb ram space is way more than the 4gb address space available via 32bits but is well within the scope of 36bits, so either I am talking twaddle and my XP 32bit SP3 with PAE is performing unlike everyone else’s or a lot of people/experts are just wrong. Its also worth noting that whenever you make a major change that affects how the HAL works then you should reinstall your OS (over the top of the old one or clean) so it works 100% correctly rather than just 80% correctly, e.g. merely putting the /PAE switch in the boot.ini and it showing PAE on the system properties>general tab is not enough just like changing the computer type in Device Manager which all intrinsically affect how the HAL is configured which con only be done on windows installation. |
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