Question: What is the main product of the company which acquired The Portland Group?

Context paragraphs:
Ruskets: Ruskets was a cereal product consisting of pressed biscuits of toasted wheat flakes.  They were produced by Loma Linda Foods, a health food company owned by the Seventh-day Adventist Church.  In 1938 the company's main product was Ruskets.  A similar item, "Weet-Bix", remains popular in many countries.

In Win Development: In Win Development is a public company in Taiwan specialising in computer enclosures.  Its has regional offices in US, UK, Netherlands and China.  The company's main product lines include computer case, power supply, rackmount and tower servers and computer storages peripheral.  The core competency of In Win is to provide computer cases to computer system integrators for government, education, and corporate segments.  In 2009, In Win started adding a new product line targeting gaming computer cases and power supply.

The Portland Group: PGI (formerly The Portland Group, Inc.), was a company that produced a set of commercially available Fortran, C and C++ compilers for high-performance computing systems.  On July 29, 2013, NVIDIA Corporation acquired The Portland Group, Inc.  The Portland Group (or PGI) name is now known as a brand of software development tools produced by NVIDIA Corporation.

Charles Corfield: Charles "Nick" Corfield is a mathematician, computer programmer, and founder of several startup companies in Silicon Valley, most notably Frame Technology Corp. in 1986, which was acquired by Adobe Systems in 1995.  While at Columbia University, Charles wrote the original version of the desktop publishing application FrameMaker, which was the main product of the company he soon co-founded.  An undergraduate at St John's College, Cambridge, he received his bachelor's degree in mathematics and physics from the University of Cambridge in 1982.  In 1996 he donated £2.5m to help fund Cambridge University's Centre for Mathematical Sciences.  The Sunday Times Rich List estimates his wealth at over £100m.

Ntractive: Ntractive is a privately held software development company based in Grand Forks, North Dakota that markets business software to small to medium-sized companies.  Established in 2006, the company's main product is Elements CRM, a Mac CRM (Customer Relationship Management) application aimed at small business that use Mac OS X computers, iPads and iPhones., Elements CRM is a cloud computing web application that employs a unique site-specific browser to merge desktop and web application functionality.  The product was first introduced to the public at a keynote address during Apple's 2007 World Wide Developer's Conference.  The official launch of Elements SBM (the products original name) 1.0 took place at Macworld 2009.  The product was then renamed to Elements CRM and with its 2.0 release was awarded the honor of Apple "Staff Pick" in July, 2009.

Main product: A main product is a joint output that generates a significant portion of the net realizable value (NRV) within a joint production process.  The classification of a product resulting from a joint production process as either a main product or a by-product has relevance in the context of cost management because costs are only allocated to main products, not to by-products.

Surrogate advertising: Surrogate advertising is a form of advertising which is used to promote banned products, like cigarettes and alcohol, in the disguise of another product.  This type of advertising uses a product of a fairly close category, as: club soda, mineral water in case of alcohol, or products of a completely different category (for example, music CD's or playing cards) to hammer the brand name into the heads of consumers.  The banned product (alcohol or cigarettes) may not be projected directly to consumers but rather masked under another product under the same brand name, so that whenever there is mention of that brand, people start associating it with its main product (the alcohol or cigarette).  In India there is a large number of companies doing surrogate advertising, from Bacardi Blast music CD's, Bagpiper Club Soda to Officers Choice playing cards.

Nervve: Nervve is a visual search company located in Buffalo, New York, USA.  The company's main product allows users to search for a specific object, scene or event within media or video.  They target their product for uses by media & entertainment, the US Department of Defense, the intelligence community, law enforcement, social media platforms and more.  Nervve is a privately held company backed by investors that include HC2 Holdings Inc. and In-Q-Tel.

Chemical Computing Group: Chemical Computing Group is a software company specializing in research software for computational chemistry, bioinformatics, cheminformatics, docking, pharmacophore searching and molecular simulation.  The company's main customer base consists of pharmaceutical and biotechnology companies, as well as academic research groups.  It is a private company that was founded in 1994; it is based in Montreal, Quebec, Canada.  Its main product, Molecular Operating Environment (MOE), is written in a self-contained programming system, the Scientific Vector Language (SVL).

Nvidia: Nvidia Corporation ( ) (most commonly referred to as Nvidia, stylized as NVIDIA, nVIDIA or nvidia) is an American technology company based in Santa Clara, California.  It designs graphics processing units (GPUs) for the gaming and professional markets, as well as system on a chip units (SoCs) for the mobile computing and automotive market.  Its primary GPU product line, labeled "GeForce", is in direct competition with Advanced Micro Devices' (AMD) "Radeon" products.  Nvidia expanded its presence in the gaming industry with its handheld SHIELD Portable, SHIELD Tablet and SHIELD Android TV.

Supporting paragraphs: The Portland Group Nvidia
Answer: GPUs