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  1. What is AGP?
  2. What is DirectSound3D?
  3. What is Dolby AC-3 surround sound?
  4. How can you differentiate P2BXA/P2LXA with other Dual Pentium II 440BX/440LX or any other mainboard?
  5. What is the difference between P2BXA and P2LXA?
  6. Could you recommend system solution using P2BXA/P2LXA?
  7. Could you explain "High-performance with high-end audio ATX mainboard" in detail?
  8. What is the major difference between Pentium III and Pentium II?
  9. I can use half price purchasing single Pentium II/III mainboard also running up to 1GHz CPU, why should I purchase P2BXA?
  10. What is ATC(Advanced Transfer Cache)?
  11. Do you want up to 2GHz Pentium III PC performance?
  12. How can I upgrade my old Pentium/II/III/4 computer? NEW


What is AGP ?

AGP, originally proposed by Intel, is high performance bus specializing for 3D graphic acceleration. The bus protocol is similar to PCI bus, but the operating frequency is 66MHz(33MHz in PCI bus) and the data transfer rate can be double(4 times on AGP2.0 version) again. The bandwidth of AGP bus under 2X mode is 528MB/sec, the AGP bandwidth without 2X mode is 264MB/sec, and the bandwidth of PCI bus is only 132MB/sec.

The graphic engine in the mid-cost or low-cost graphic chip is rather slow compared with AGP or PCI bus speed, that is the reason why the performance of AGP version of same graphic chip is only slightly more than that of PCI version. This case is just like SCSI interface compared with IDE interface on hard drives. But state of art 3D graphic chipsets such as  nvidia TNT or beyond series(Ironically the latest GeForce series has built-in powerful graphics processor unit, the demanding for higher AGP2.0 bus speed is not obvious.) are already benefit from higher AGP bus speed, and various kinds of AGP version graphic card dominate the market of graphic card. Remember the first AGP graphics card emerged only four years ago---Fall of 1997.

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What is DirectSound3D ?

DirectSound3D, proposed by Microsoft, is new audio API between application program and device driver. It will provide numerous audio management capabilities, include 3-D positioning. 3D positioning audio gives the listeners the impression that sounds are coming from all directions. This feature is standard for Windows 98 and Windows 2000. P2BXA/P2LXA has hardware acceleration function of 3D positioning audio, which will be much better than software acceleration only.

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What is Dolby AC-3 surround sound ?

Dolby Laboratories is a pioneer of developing surround sound since 70's cinema era. In 80's there is 3-channel surround sound and famous Pro Logic 4-channel surround sound. In 90's Dolby proposes and patents AC-3(or name as 5.1 channels)  surround sound, which uses left, center, right, left surround, right surround and subwoofer channels by using digital signal processing. First used on cinema in 1992, then on laser disc in 1995, and then on DVD in 1997. For home theater application DVD and Dolby AC-3 surround sound has been de facto standard. P2LXA-D/P2BXA-D has already built-in Dolby AC-3 surround sound decoder and amplifier, so there is no need to purchase expensive external Dolby AC-3 decoder/amplifier unit.

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How can you differentiate P2BXA/P2LXA with other Dual Pentium II 440BX/440LX or any other mainboard ?

P2BXA/P2LXA is true high performance, multitasking computer mainboard. In Windows NT multiprocessor environment(please note Windows 95/98 is uniprocessor environment, there is no benefit from dual processors) some software will take advantage from dual-CPU configuration and accelerate performance. The CPU can be 233~450MHz Pentium II CPU(and also 450MHz~1GHz Pentium III), up to 333MHz Pentium II or 400MHz Celeron Slot 1 version CPU for P2LXA. (Celeron not supports dual-processor capability, not recommending for P2LXA or P2BXA high-performance mainboard.)

And P2BXA/P2LXA is not only a fast and multitasking computer mainboard, but also with full strength capability on multimedia applications. True-stereo microphone input can provide your home studio by using premium studio microphone. Wavetable synthesizer and DirectSound3D makes your MIDI playback, business presentation and 3D game more real. Bundled Voyetra Technologies Digital Orchestrator Pro advanced MIDI/digital audio recording/editing/processing/ playback tools makes you do virtually anything in digital music and digital audio works. Also bundled AudioStation 2 popular MIDI/digital audio recorder/player/basic editor & processor, and BeYoung Technology innovative and vivid MPC Smart Guide---multimedia tutor and testing tool and 3D Exploration Kit---3D graphics tutor and testing tool.

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What is the difference between P2BXA and P2LXA?

The only difference is that P2BXA can support up to 450MHz Pentium II CPU and also 450MHz~1GHz Pentium III and use 100MHz SDRAM when using beyond 350MHz(include) CPU, P2LXA only supports 66MHz SDRAM and up to 333MHz Pentium II CPU(and also up to 400MHz Celeron Slot 1 version CPU), which is the highest CPU operating frequency for all Intel 440LX-based mainboard; else performance and features are same, even bundled same application softwares and drivers of latest version.

The CPU performance is proportional to the CPU frequency(with same or similar processor architecture and cache size/speed if comparison is based on CPU of different models); the 2D/3D graphics performance(suppose using premium graphics card) is roughly proportional to CPU speed, for example on 600MHz is about 78% more than that on 333MHz, graphics performance on 550MHz is about 65% more than that on 333MHz, graphics performance on 500MHz is about 52% more than that on 333MHz, graphics performance on 450MHz is about 35% more than that on 333MHz, graphics performance on 400MHz is about 25% more than that on 333MHz; the hard disk performance on 400~550MHz is about 5~15% better than that on 333MHz.

333MHz Pentium II CPU uses same new chip manufacturing technology(0.25m) as 350~450MHz Pentium II and also 450~600MHz Pentium III CPU(600MHz+ Pentium III uses 0.18m technology, on the contrary 233~300MHz Pentium II CPU uses older(0.35m) technology. It means that 333MHz Pentium II CPU uses same lower CPU voltage(2.0V) as 350~450MHz Pentium II CPU and same lower power consumption(less than 30W). On the contrary 233~300MHz Pentium II CPU use 2.8V with higher power consumption(35 to 45W). The power consumption of 300MHz Pentium II CPU will be around 45W under full running, that of 333MHz Pentium II CPU will be only 24W under same full running(actually the lowest power consumption one in all Pentium II CPU family). The best and worst selections of Pentium II CPU is only one step difference, beware of this fact.

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Could you recommend system solution using P2BXA/P2LXA?

For budget solution(around $1100, include monitor) you can use either P2BXA, 850 MHz Pentium III CPU, premium AGP graphics card(This is the most important performance-affecting system component except CPU, please see the description in the following paragraph.), 8GB~40GB IDE Ultra DMA hard drive(faster access time preferred), 64MB SDRAM(if CAD or multimedia design 128 MB preferred), 24X+ CD-ROM drive(DVD preferred), floppy drive, PS/2 keyboard, PS/2 mouse, 56K modem(the fatest modem which can be obtained from analog phone line, higher speed can be obtained through dedicated digital line and DSL modem emerged recently), a pair of non-powered speaker(Platinum Sound PS341 or equivalent) or powered speaker system include subwoofer(Cambridge SoundWorks Ensemble IV or equivalent)**, ATX case and 15" or 17" monitor. You will get best audio and 3D/2D graphics performance and features for best price.  

Regarding the premium AGP graphics card, nvidia GeForce3 is currently the fastest 3D graphics accelerator, much faster than that of 2nd-rank nvidia GeForce2. And 3DWinbench2000 performance of GeForce 256(3rd-rank) is already three times better than 4th-rank graphics chipset---Riva 128 TNT 2 (ULTRA), which has similar 3D/2D performance to 3dfx interactive Voodoo3, both are almost twice 3D performance to that of previous 3D performance leader---nvidia Riva 128 TNT and ATI Rage 128GL, but the 2D performance is still similart to that of previous leader. nvidia Riva 128 TNT is one of the best of all 3D/2D graphics chipset in Q1 1999(the other one of the best is ATI Rage 128 GL, which is announced several month ago and has similar 2D performance of Riva 128 TNT, and roughly similar 3D performance of Riva 128 TNT(3DWinbench99 of Rage 128 GL is better than that of Riva 128 TNT, but 3DWinbench98 of Rage 128 GL is worse than that of Riva 128 TNT) and 3 times(3D performance) faster than ATI previous version---Rage Pro. ATI is famous for rich-featured graphics card such as TV output, MPEG-2 playback, Video capture and TV tuner features.), the performance of graphics card based on TNT chipset is about 50~70% more than 2nd-ranked graphics card based on other chipset(Intel I740 or original nvidia Riva 128, which are best before TNT emerges) on 3D graphics Winmark under DirectX6, around 15% more on 2D graphics Winmarks at 450MHz and also with better quality. 3dfx interactive a couple month ago released Voodoo3 chip-based 3000 AGP graphics card, which is the fastest 3D graphics card(similar performance to Diamond Multimedia V770 AGP graphics card based on nvidia Riva 128 TNT 2 chipset, which is released almost same time frame) of all graphics card right now. Please note that AGP(or PCI) graphics cards using different 3D/2D accelerator chipset may have more than 10 times performance difference on 3D and significant performance difference on 2D. The more expensive graphics cards are not necessary to have better performance. Even different graphics cards using same graphics chipset may have significant performance difference and lack some features because of different VGA BIOS and driver, and manufacturers of graphics card are always busy to update their drivers, so please always download the latest driver from their web.

For more complete solution you can use DVD package(DVD drive and MPEG-2 decoder card) instead of CD-ROM drive, please note some graphics card incompatible with some MPEG-2 decoder card (because new MPEG-2 decoder card using videoInlay technology which is not supported by hardware or driver of some graphics card). You can enjoy high-quality DVD movies, and the total system solution costs around $1250. If you use software MPEG-2 decoder, you can save around $100(the DVD with software decoder solution is just around $50 higher than that of brand name x48 CD-ROM drive solution). The drawback of software decoder is high CPU utilization rate, it will impact performance of running complex job on background while watching DVD movie.

And color inkjet printer is almost mandatory for any computer work, you can only pay less than $150 getting 720 or 1440 dpi vivid color printouts. Scanner is probably next item you will consider, most 1200 dpi scanner is under $100, and SCSI or USB preferred since it is much faster than the parallel-port model. Digital camera is very convenient in the web or multimedia design works, now the price of high-end models(over 1Meg pixels) drops significantly in the past year. For multimedia design probably you need ZIP drive($100~$150) in order to tranfer your work to other people.

Except intensive high-speed hard drive applications such as graphic design, animation, picture process or video editing(data file size over 100MB is very popular, compared to usually less than 1MB data file size of word processor, spread sheet of business applications), SCSI hard drive solution is not recommended. Since it needs to pay extra $200~$600 for SCSI adapter and SCSI HD with only standard speed and obtains virtually same performance as IDE HD. Because the bottleneck of hard drive performance is on-track seek and read/write time(average 5.5~12ms) and also track to track seek time(0.8~2.5ms) of magnetic head in modern hard drive unit, both ultra wide SCSI(bus bandwidth = 40MB/sec) or ultra DMA IDE(bus bandwidth = 33MB/sec) are so fast that they virtually do not influence the performance of standard hard drive. Therefore, the high performance SCSI hard drives use higher rotating speed(7200 rpm or even 10,000 rpm, on the contrary almost all IDE drives use only 5400 rpm until 1999) to obtain higher performance. By using high rpm SCSI HD the high-end(graphic, picture and video intensive) disk performance in Winbench98 may be over 4 MB/sec, that of most IDE HD usually are 3~4 MB/sec. But the high speed HD usually has thermal issue and needs better chassis fan, on the contrary the standard HD even does not need chassis fan.

Since 2000 the high-density disk plates have a lot of progress, the internal transfer rate increases gigantically. It is the first time in hard drive history the bottle neck of hard drive read/write speed swings more or less from rotating speed or any other mechanical constraint to bus protocol speed. Currently for business or daily-life files size there is no difference between ATA33 and ATA66 or ATA100(Hard drive technology still can not benefit from 100MB/sec bus protocol speed at present) because invloving a lot of random read/write small files which mechanical constraints still dominates. But if you involve the multimedia design(big file size), the ATA66 or ATA100 may be the better choice.

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Could you explain "High-performance with high-end audio ATX mainboard" in detail?

First let us discuss "High-performance", then "high-end audio", and then "ATX".

A. High-performance

High-performance is not only running 1GHz Pentium III CPU, it should have running dual-processor capability. Windows 95, 98 or ME(Millennium Edition) is uniprocessor OS environment, it means two CPU running under Windows 95, 98 or ME with no performance benefit and meaningless. But Windows 2000(based on NT technology) or NT is true multiprocessor OS environment, meaning two CPU can have performance benefit; the performance increase depends upon parallel processing degree of tasks and software.

Tasks of most of simple computer work, like word processor, playing game or web browsing are near pure sequential; on the contrary tasks in network or internet server are almost independantly parallel degree. That is the reason why computers in home, business or professional works are almost single processor machines, on the contrary servers always use two, four or more  processors systems.

But as computer tasks grow more and more complex with multimedia applications, most of computer tasks have more and more parallel degree. Under Windows 2000 or NT dual-CPU configuration these works will have significant performance increase. By running Winston99 dual-processor inspection tests suite(using high-end MicroStation, Adobe photoshop and Microsoft Visual C++) 233MHz dual CPU in P2LXA or P2BXA platform has similar performance compared to 333MHz single CPU at P2LXA or P2BXA platform, and 333MHz dual CPU at P2LXA or P2BXA platform has similar performance compared to 450MHz single CPU at P2BXA platform, and 550MHz dual Pentium III at P2BXA platform has similar performance compared to 850MHz single Penyium III at P2BXA platform.. The individual performance benefit of each subtest will be 30%, 15%, 50% for Microstation/CAD, Adobe Photoshop/Multimedia design, Microsoft Visual C++/Software design compared dual CPU configuration to single CPU configuration under 550MHz Pentium III CPU. If you are running Visual C++ environment, the performance even can be as high as double by using multi-threads/multiple process and subdividing tasks equally.

And most important the lower speed CPU will gain more performance benefit under dual CPU configuration, so you should never give up your P2LXA board. On the other hand the price of high speed CPU is very expensive initially and drops very fast within one year, you can install one high speed CPU first and then several months or a couple year later install another same speed CPU, which is already very cheap, to upgrade as dual CPU configuration by minimum cost.

Please note that the dual CPU configuration of Windows 2000 or NT will setup automatically first time when installed NT with 2 CPU, that means if you install Windows NT with one CPU initially when upgraded 2nd CPU later you need to re-install Windows NT again with 2 CPU. So maybe the best strategy you can start to install from Windows 98 or ME with single CPU enjoying rich multimedia and internet features, and then several months or a couple year later you want higher performance, you can upgrade to Windows 2000 or NT with 2nd CPU and still keep everything good stuff of Windows 98 or ME.

B. high-end audio

PCI audio may support DirectSound3D (latest standard of 3D audio, for 3D game or high-end business presentation) hardware acceleration and synthesized wavetable sound(true music instrument sound when MIDI playback, much better than low-cost FM synthesized sound).

And PCI audio may have very good CPU utilization, the less CPU utilization of any I/O device, the faster the total computer performance we can obtain. Under AudioWinbench99 based on 44.1KHz sampling frequency, 16 bit quantizing level, 32 voice paramemters, for P2BXA or P2LXA board the CPU utilization of DirectSound will be ~0 at 500MHz(Pentium III), less than 0.25% at 450MHz, 0.5% at 333MHz, 1.0% at 233MHz; that of DirectSound3D will be less than 6% at 500MHz(Pentium III), 7% at 450MHz, 10% at 333MHz, 14% at 233MHz. On the other hand for ISA audio card the CPU utilization of DirecSound will be 5~12% at 233~450MHz CPU speed; that of DirectSound3D will be 30~90% at 233~450MHz CPU speed.

Before deciding PCI audio you need to double check whether it supports DirectSound3D hardware acceleration and synthesized wavetable sound. Some low-cost PCI audio card does not support DirectSound3D hardware acceleration and synthesized wavetable sound.

Even if it supports DirectSound3D hardware acceleration and synthesized wavetable sound, check whether it has built-in DSP(Digital Signal Processor) to process these feature. Some cost-effective PCI audio chips or card use CPU to process these features, which will increase CPU utilization significantly just like ISA audio card.

P2BXA or P2LXA uses Crystal Semiconductor CS4610-----best and fastest PCI DSP-based audio chipset, which features SLIMD modified dual Harvard architecture. The DSP core  is rated 300 MIPS with 100MHz internal clock frequency and includes two Multiply-Accumulate(MAC) blocks and one 16 bit Arithmetic and Logic Unit(ALU). This DSP is capable of running many DSP algorithms simultaneously, the high concurrency capability is valuable for applications such as immersive 3D game or vivid business presentation, which may play a lot of DirectSound and DirectSound3D audio streams and MIDI music sequences concurrently.

Then consider codec/mixer/amp circuits-----interface between outside world and PCI audio chip, check frequency response/distortion/crosstalk/noise/microphone sensitivity/stereo microphone support/power amplifier present. If all of these spec and features have passed, then you can say you have high-end audio feature.


For past 15 years the majority of PC motherboard formfactor is always AT(virtually baby AT). Today AT formfactor still dominates motherboard, but there are ATX, LPX, NLX, WTX or proprietary formfactors sharing the formfactor market. LPX formfactor is for slim or compact PC, which is gradually phased out. NLX is new standard which is not popular and very expensive. And WTX is in introductory phase and it is server-oriented. ATX formfactor has several advantage over AT formfactor, such as better thermal environment, easy-access backpanel connectors and power control/management function(AT does not have this function). So it grows very fast during past six years, right now ATX has dominated all PC market and AT is virtually obsolete.

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What is major difference between Pentium III and Pentium II?

For physical and compatibility viewpoint you can not find any difference, Pentium III can use at any previous Pentium II 440BX mainboard without any modification(of course old BIOS still shows "Pentium II" not "Pentium III" text string on screen while booting, but that is not problem).

The strong point of Pentium III is additional streaming SIMD(Single Instruction Multiple Data) instructions which are very powerful on high-end multimedia applications such as 3D graphics, digital video, video codec, etc. Unfortunately you need new softwares and drivers using new Pentium III instructions in order to obtain dazzling performance. Usually it takes several months or a couple years to emerge and ramp, which is somewhat like MMX history four years ago.

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I can use half price purchasing single Pentium II/III mainboard also running up to 1GHz CPU, why should I purchase P2BXA?

First you never have any chance upgrade to Dual-CPU computer and enjoy 15~50% performance increase(or even up to double performance heavily dependant upon parallel degree of computer jobs) under Windows 2000/NT or Linux operating systems(please refer to FAQ#8).

Second you need to purchase a separate audio/sound card(virtually no Pentium II mainboard with built-in audio function, even if it has, is it best one?). A good audio/sound card should be high-speed DSP-based with wavetable sound PCI card and usually it is not cheap. And then is it supporting stereo-microphone(almost no audio/sound card with this feature), built-in stereo power amplifier(5W RMS power output at 3 ohm speaker impedance per channel, or 40W music peak power per channel) and DOS game audio legacy(Remember old-fashioned game? It is still worth playing again sometimes.)? Finally we are sure that it does not have internal monitoring function(only associated on-board audio), which is very convenient without external speaker.

Third you don't have latest and full version of #1 digital audio/MIDI editing & processing softwares and #1 Multimedia/3D graphics tutor and testing software. Until now no any audio/sound card bundles so complete softwares. And if you want to purchase it from retail stores, it costs you $400!

Fourth you probably don't have on-line measurement/display of various board-voltages and speeds of all fans and board temperature, chassis intrusion detector, power interrupt recovery and complete IR protocol(include fast IR and comsumer IR), these features are only associated with high-end mainboards, and even high-end mainboards are not loaded with all these features.

Finally you should know that most expensive component of Performance PC($1000~$2000 PC, versus sub-$1000 Value PC) is CPU[It means that it does not make any sense by using 1GHz Pentium III CPU on low-cost(and also not high-performance and not rich-featured) mainboards]. The most performance-influential component is graphics card. Not all IDE hard drives are with same performance. And SCSI hard drive is no more practical in desktop computer. If you only purchase "half-priced" single Pentium II mainboard to build your performance computer system and think already saving your money, chances you will pay more in whole system and lacking a lot of features, even inferior performance. Please follow the suggestions of FAQ #7 to plan your high performance computer system.

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What is ATC(Advanced Transfer Cache)?

ATC uses full-speed cache just like Xeon CPU and it is on-chip cache although only 256KB size, all standard Pentium III and II use half-speed and 512KB size cache(The cache of Celeron, not only not-supporting dual processor capability, is even 128KB and half-speed also). The CPU performance of ATC version Pentium III is faster than standard Pentium III about 20%, graphics performance about 10~20%, hard drive performance about 5%. All 650+MHz Pentium III are ATC version, 550 and 600MHz have both versions. All ATC version Pentium III use 0.18m or 0.13m technology, it means using lower voltage(1.65V or lower) and most important---lower power.

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Do you want up to 2GHz Pentium III PC performance?

Although Intel announced 3.2GHz Pentium 4 processor on June 2003 with HyperThreading technology(logically dual processor configuration inside), it only supports single physical processor  and is power-hungry CPU[even the lowest 1.3GHz version of Pentium IV consumes more than twice power of  Pentium III @1GHz] and has super long pipeline[20 vs. 10 for Pentium III], which is high-performance for streaming video processing[It is one of the most processor power demanding computer work, but if you do not intend to do such work you don't need Pentium IV. The situation is just like 3D graphics card, if you don't do any 3D CAD job or play 3D game you really don't need 3D graphics card.] but not good for all other computer tasks because frequently flushing this pipeline for any heavy-branching software, which is the real case for any other computer jobs, will sacrifice performance for all other computer works.

Dual processor in desktop computer is matured technology(Ziff-Davis has dual processor inspection tests since November 1998) and gets high performance under Windows 2000 professional edition(the lowest level version of Windows 2000, all other three higher level versions are dedicated for servers, high performance servers and large scale servers). Windows 2000 is based on Windows NT technology and is the most reliable and the highest performance Windows ever and keeps rich features and user friendly interface of Windows 98/ME. Recently the dropping price of top speed CPU and growing popularity of dual-processor supported high-end application software push the high-performance dual processor-based desktop computer more and more practical. Right now dual 1GHz computer system can run up to 2GHz PC performance, XCV is the only expert in this domain.

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How can I upgrade my old Pentium/II/III/4 computer? NEW

Regarding to CPU you can try to find bigger and faster L2 cache memory (level two cache compared to level 1 cache, closed to arithmetic logic unit, which is usually 64KB) version, all processors after Pentium III include current Core series CPU benefits performance advantage from L2 cache size. There is no L2 cache in original Pentium CPU. Pentium II is the first CPU associated with L2 cache which is too big to fit CPU package at that time. So it needs create cartridge CPU module mounting CPU package and two of 256KB half CPU speed L2 cache memory (SRAM) packages. If using Pentium II/III computer try to use ATC version CPU which has full speed (but half size) L2 cache and will have significant performance boost.

For memory you can fully populate all memory slots which will accelerate some performance. For 2D graphics it is matured on late '90 so there is no need to upgrade. And you won't consider playing 3D game on your old computer.

The most significant performance can be obtained from hard drive which has 10+ times performance increase during past decade. And you can fully use this advantage now with your old computer. Current PATA (IDE) hard drive can deliver over 100MB/s performance which will fully use old IDE bus speed; 66MB/s, 33MB/s or 16.5MB/s.

Don't forget PCI bus you can install PCI SATA card (there is some trick for driver installation and may not fit for all old computer) and watch dramatically performance increase. If your computer still uses USB v1.00, upgrade PCI USB v2.0 adapter which will accelerate printer/scanner, picture download and video camera vigorously.

If you have internet connection with other newer PC but not on this one, get connected by installing network connection. Throw away bulky CRT monitor and replaced by LCD/LED monitor with much much less space requirement and power consumption. Pentium series computer is the most expensive computer era during PC history which was $1,000~$2,000, only second to very early stage of IBM PC while there is no clone computer appeared. You will amaze what a small money makes your old computer working like new computer for daily operation.

*Dolby AC-3 decoder and 6-channel amplifier are only available in P2LXA-D or P2BXA-D OEM version.

**For even better sound performance you can consider Cambridge SoundWorks Ensemble II(best one) or III subwoofer/satellite speaker system.

More questions?  Please e-mail to techsupport@xcvcorp.com

Copyright [XCV Corp., Inc.] All rights reserved.
Revised: July 5, 2003 except marked as new which is updated on July 30, 2011