[harik]

@JonusC wrote:

with a little trick you can allocate more then 3GB by PAE ( physical address extensions ) and optionally ( on my board ) there is an option for it 🙂

That won’t work for me since I have a 1GB PCI-e v2.0 graphics card. I’ll actually get ~2.8GB max with this card if I only ran 32-bit, otherwise I will have to start pulling out wireless card/firewire controller/USB hubs/mouse/etcetera 😛 And BTW, PAE slows your CPU down because it has to translate 32-bit calls to 36-bit calls with every memory request. Try it – do a CPU becnhmark in Everest with PAE on, then repeat with it switched off.

EDIT: 32-bit OS’s also can’t use Hardware Virtualization featuresets. VMWare, Virtual XP Mode in Windows 7 and the exotic nature of encoding my DVD’s to WMV for Windows Media Center with CUDA acceleration, they are all faster in 64-bit. So is DXVA playback – I couldn’t imagine playing a BluRay movie on one monitor while working in Adobe CS4 on the main one in 32-bit 😉

Well, a few corrections. Vista 32 does use PAE – in fact, it’s a hardware requirement to use Data Execution Prevention – you need the 64bit TLB registers. So you’re translating all 32bit addresses to 64bit registers in the TLB anyway (unless you specifically boot a no DXP 32bit kernel). Secondly, vista32, while having PAE enabled for 99% of users, does happily ignore any reported RAM above the 4gb mark. This means if your BIOS remaps 1gb of RAM to 5gb to make room for the videocard, you’re capped at 3gb. It’s actually an identical kernel to server 2008, there’s a single license key that unlocks >4gb on 32bit processors.

You’re partially correct about virtualization as well – there are hardware VT extensions in 32bit processors (or 64bit in 32bit host mode), but they’re not as complete as the 64bit AMD set (Intel is (was?) missing some of the IO virtualization, moving more of the work into the hypervisor. VMware refuses to use the 32bit extensions, but Virtualbox does (apparently, I haven’t tested).

I’d imagine that running a modern dualcore CPU with a decent videocard could play a bluray (GPU decoding offload) on one monitor while running CS3/CS4 on the other – in either 32 or 64bit mode.

Aside from those minor nits, I agree with you.

[Author]

Posts